Pope Francis, the first Latin American leader of the Roman Catholic Church, died on Easter Monday after suffering a stroke and cardiac arrest, the Vatican says, ending an often turbulent reign in which he sought to overhaul an ancient and divided institution.

He was 88, and had suffered double pneumonia this year, but his death came as a shock after he appeared in St. Peter's Square in an open-air popemobile to greet cheering crowds on Easter Sunday, suggesting his convalescence was going well.

Pope Francis chose to be buried in Rome's St. Mary Major Basilica. – AP

"Dear brothers and sisters, it is with profound sadness I must announce the death of our Holy Father Francis," Cardinal Kevin Farrell announced on the Vatican's TV channel.

"At 7:35 (0535 GMT) this morning the Bishop of Rome, Francis, returned to the house of the Father."

Cardinals were due to meet on Tuesday to plan Pope Francis' funeral, which leaders from around the world will attend ahead of a conclave next month to elect a new head of the Roman Catholic Church.

His sudden death set in motion ancient rituals, as the 1.4-billion-member Church started the transition from one pope to another, including the breaking of the pope's "Fisherman's Ring" and lead seal so they cannot be used by anyone else.

Cardinal Mauro Gambetti  led prayers in St Peter's Square on Monday evening.

"We want to thank the Lord for the gifts he has given to the whole Church with the apostolic ministry of Pope Francis, a pilgrim of hope," he said.

All cardinals currently in Rome have been invited to gather in the Vatican on Tuesday morning to make funeral plans.

Crowds attend a rosary for Pope Francis in St Peter's Square following his death. – Reuters

US President Donald Trump, who clashed repeatedly with the pope about immigration, said he and his wife would fly to Rome for the funeral. Among other heads of state set to attend were Javier Milei, president of Francis's native Argentina.

The Vatican has said it expects the ceremony to take place sometime between Friday and Sunday. In a break from tradition, Francis confirmed in his final testament released on Monday that he wished to be buried in Rome's Basilica of Saint Mary Major and not St Peter's Basilica.

The gathering of cardinals will also review the day-to-day running of the Church in the period before a new pope is elected.

A conclave to choose a new pope normally takes place 15 to 20 days after the death of a pontiff, meaning it should not start before May 6. Some 135 cardinals are eligible to participate in the highly secretive ballot which can stretch over days.

At present there is no clear frontrunner to succeed Francis.

Trump remembers Pope Francis as 'a good man'. – AP

Francis died of a stroke and irreversible cardiovascular arrest, Vatican doctor Andrea Arcangeli said in the death certificate, which was released by the Vatican. It added that the pope had fallen into a coma before he died.

Besides his recent lung infection, Arcangeli said Francis had also suffered from high blood pressure and diabetes.

A Vatican spokesman said the pope's coffin might be moved to St Peter's Basilica as early as Wednesday morning to allow the faithful to pay their respects.

Francis' native Argentina ordered seven days of mourning, as did neighbouring Brazil.

"The pope of the poor has left us, the pope of the marginalised," said Jorge Garcia Cuerva, the archbishop of Buenos Aires, a position Francis once held.

Francis had on Sunday made his first prolonged public appearance since being discharged from hospital on March 23 following a 38-day stay for pneumonia, occasionally waving to onlookers and greeting a child who was brought to his side.

In an Easter Sunday message read aloud by an aide as the pope looked on from the main balcony of St. Peter's Basilica, the pontiff had reiterated his call for an immediate ceasefire in Gaza – a conflict he had long railed against.

Archbishop of Vancouver remarks on death of Pope Francis. – AP

At the Vatican, locals, tourists and pilgrims visiting for Easter expressed their shock and grief.

"This is something that really hits you hard," said Emanuela Tinari from Rome. "He was a pope who brought so many people closer to the church. He was not appreciated by everyone. But he definitely was by ordinary people."

Final meetings 

Doctors had prescribed two months of rest when the pope left hospital last month but he appeared on a number of occasions. Francis met Britain's King Charles in April and had a brief meeting on Sunday with visiting US Vice President JD Vance.

"My heart goes out to the millions of Christians all over the world who loved him," Vance said on X.

World leaders praised his efforts to reform the worldwide Church and offered condolences to the world's 1.4 billion Catholics.

"He was a good man, worked hard. He loved the world," said Trump, whom the pope had criticised in the past, especially for his hardline on immigration.

Pope Francis appears during Easter Mass at the Vatican on Sunday. – AP

Italian Prime Minister Giorgia Meloni mourned the departure of "a great man, a great shepherd".

"I had the privilege of enjoying his friendship, his advice, his teachings, which never ceased not even during times of trial and suffering," Meloni said.

The outspoken president of Argentina, Javier Milei, had clashed with the pope in the past, branding him at one point the devil's representative on earth. But he changed his tune after taking office in 2023 and mourned his death.

"Despite differences that seem minor today, having been able to know him in his goodness and wisdom was a true honour for me," Milei said on X.

British Prime Minister Keir Starmer joined "millions around the world in grieving the death of His Holiness Pope Francis".

Pope Francis' final appearance on Easter Sunday. – Reuters

"His leadership in a complex and challenging time for the world and the church was courageous, yet always came from a place of deep humility," Starmer said.

French President Emmanuel Macron spoke of Francis's dedication to the poor.

"Throughout his pontificate Pope Francis had always sided with the most vulnerable and the most fragile, and that he did this with a lot of humility," Macron said.

"In this time of war and brutality, he had a sense for the other, for the most fragile."

Russian President Vladimir Putin hailed Francis as an outstanding man, the Kremlin said. 

Ukrainian President Volodymyr Zelensky said he knew how to foster unity and give hope.

Australian PM Anthony Albanese after paying his respects to the pope at St Patrick’s Cathedral In Melbourne. – AAP

Australian Prime Minister Anthony Albanese said the first Pope from the Southern Hemisphere Francis was close to the people of Australia. 

"For Australian Catholics, he was a devoted champion and loving father," Albanese said.

Opposition Leader Peter Dutton also expressed his condolences.

"He lived frugally and simply,'' Dutton said. "Above all else, he was driven by Christ's values of mercy and forgiveness." 

Many global leaders were expected to attend his funeral. In a break from tradition, Francis confirmed in his final testament that he wished to be buried in Rome's Basilica of Saint Mary Major and not St Peter's Basilica.

Crowds attend a rosary for Pope Francis in St Peter's Square following his death. – Reuters

A conclave to elect a new pope normally takes place between 15 and 20 days after the death of a pontiff. Some 135 cardinals are eligible to take part in the highly secretive ballot which can stretch over days. At present there is no clear frontrunner to succeed Francis.

Born Jorge Mario Bergoglio, the Argentine cleric's election as pope on March 13, 2013, surprised many observers who had seen him as an outsider.

He sought to project simplicity into the grand role and never took possession of the ornate papal apartments in the Apostolic Palace used by his predecessors, saying he preferred to live in a community setting for his "psychological health".

He initiated changes within the Vatican, emphasising transparency, accountability and financial reform, and appointed more women to senior posts in its hierarchy. However, Francis was also viewed as a haphazard leader, often blindsiding Vatican officials with his off-the-cuff comments.

He inherited a Church torn by infighting in the Vatican bureaucracy, and was elected with a clear mandate to restore order.

But as his papacy progressed, he faced criticism from conservatives, who accused him of trashing cherished traditions. He also drew the ire of progressives, who felt he should have done much more to reshape the 2000-year-old Church.

Pope Francis prays in front of the Western Wall in Jerusalem's Old City in 2014. – AP file

While he battled with internal dissent, Francis became a global superstar, drawing huge crowds on his many foreign travels as he tirelessly promoted interfaith dialogue and peace, taking the side of the marginalised, such as migrants.

Argentines held a special Mass and lit candles on Monday, mourning in shock for their countryman.

The Mass was held in the cathedral in Buenos Aires, where Francis was once archbishop. The building was adorned with a photo of the pontiff, bunches of white flowers and the blue and white flag of Argentina.

"He insisted on building bridges, he insisted that we live in universal brotherhood," said Archbishop Cuerva.

"The pope was our father, the father of the poor, the father of mercy. The best tribute we Argentines can pay to Francis is to unite."

Unique in modern times, there were two men wearing white in the Vatican for much of Francis' rule, with his predecessor Benedict opting to continue to live in the Holy See after his shock resignation in 2013. Benedict, a hero of the conservative cause, died in December 2022.

Francis appointed nearly 80 per cent of the cardinal electors who will choose the next pope, increasing the possibility that his successor will continue his progressive policies, despite the strong pushback from traditionalists.

The Vatican said a ceremony planned for Sunday, April 27, when Carlo Acutis was to become the first Catholic saint of the millennial generation, had been postponed.

What happens when a pope dies?

With the death of Pope Francis the Roman Catholic Church will begin elaborate rituals steeped in tradition that mark the end of one papacy and lead to the start of the next.

Most are governed by a constitution known as Universi Dominici Gregis (Of the Lord's Whole Flock) approved by Pope John Paul II in 1996 and revised by Pope Benedict XVI in 2007 and 2013.

A cardinal known as the camerlengo (chamberlain) – currently Irish-American Cardinal Kevin Farrell – will run the ordinary affairs of the nearly 1.4 billion-member Roman Catholic Church during the period known as the "sede vacante" (empty chair).

He officially confirms the pope's death, a simple matter these days involving a doctor and a death certificate. Until sometime in the 20th century, this was ritually done by tapping a silver hammer on the pope's forehead three times.

The camerlengo and three assistants chosen from among cardinals under 80 years of age, known as cardinal electors, decide when the pope's body is to be taken into St Peter's Basilica for the public to pay their respects.

They also make sure the pope's "Fisherman's Ring" and his lead seal are broken so they cannot be used by anyone else. 

AP Explains: Pope Francis carried out his duties and met with believers until the end. – AP

The camerlengo locks and seals the pope's personal residence. In the past, this was in apartments in the Apostolic Palace but Francis lived in a small suite in the Vatican guesthouse known as Santa Marta.

The camerlengo and the other cardinals cannot make major decisions affecting the Church or change its teachings. The heads of most Vatican departments resign until the new pope confirms or replaces them.

Mourning rites last nine days, with the date of the funeral and burial to be decided by the cardinals. Universi Dominici Gregis says they should start between the fourth and sixth day after his death.

Pope Francis, who shunned much of the pomp and privilege of leading the global Catholic Church, modified and simplified the papal funeral rites in 2024.

The funeral Mass is still expected to be held in St Peter's Square, but unlike many predecessors, Francis asked to be buried in Rome's St Mary Major Basilica to be near his favourite icon of the Madonna.

Francis also asked to be buried in a simple wooden casket, unlike predecessors who were buried in three interlocking caskets made of cypress, lead and oak.

He asked that his body not be put on display atop a raised platform, or catafalque, in St Peter's Basilica for visitors in Rome to view, as was the case with previous popes.

AP Explains: The death of a pope initiates a centuries' old ritual to elect a new pontiff. – AP

Cardinals from around the world descend on Rome following the death of a pontiff. They hold daily meetings known as general congregations to discuss Church matters, and lay out the characteristics each believes the new pope should have.

Cardinals aged 80 or over can attend the general congregations but are not allowed to enter the conclave to choose the next pope, which is a gathering of cardinals under the age of 80.

Much of the discussion takes place in personal interactions between the cardinals.

Traditionally, a mourning period of 15 days is observed before a conclave can begin. Before he resigned in 2013, Pope Benedict modified the constitution to allow it to begin sooner if the cardinals chose to, or a maximum of 20 days after the death if some cardinals have difficulty getting to Rome.

The conclave is held in the Sistine Chapel. Until the two conclaves in 1978 that elected John Paul I and John Paul II, the cardinals stayed in makeshift rooms around the Sistine Chapel.

Since the 2005 conclave that elected Pope Benedict, they have voted in the Sistine Chapel but stayed in the Santa Marta guest house, which has about 130 rooms. Santa Marta is sealed off and they are taken by bus to the Sistine Chapel.

The word conclave comes from the Latin for "with a key". It stems from a tradition that started in the 13th century where cardinals were locked up to force them to decide as quickly as possible and limit outside interference.

These days the participants are prohibited from any communication with the outside world. Phones, internet, and newspapers are not allowed and Vatican police use electronic security apparatus to enforce the rules.

Except for the first day of the conclave, when there is one vote, the cardinals vote twice a day.

A majority of two-thirds plus one is needed for election. If no one is elected after 13 days, a run-off is held between the two leading candidates but a two-thirds plus one majority is still needed. This is to promote unity and discourage seeking compromise candidates.

When the conclave has elected a pope, he is asked if he accepts and which name he wishes to take. If he declines, the procedure starts again.

The new pope dons white vestments that have been prepared in three sizes and sits on a throne in the Sistine Chapel to receive the other cardinals, who pay homage and pledge obedience.

The world will know that a pope has been elected when an official burns the paper ballots with special chemicals to make white smoke pour out of the chapel's chimney. Black smoke indicates an inconclusive vote.

The senior elector amongst the cardinal deacons – currently French Cardinal Dominique Mamberti – steps on to the central balcony of St Peter's Basilica to announce to the crowds in the square "Habemus Papam" (We have a Pope).

The new pope then appears and gives the crowd his first blessing as pontiff.