Ukrainian President Volodymyr Zelensky has praised Ukraine's Security Service for a "brilliant operation" aimed at "military targets" on Russian territory.

A Ukrainian drone attack destroyed more than 40 Russian planes deep in Russia’s territory, a Ukrainian security official said, while Russia pounded Ukraine with missiles and drones a day before the two sides meet for a new round of direct talks in Istanbul.

A military official, who spoke on condition of anonymity to disclose operational details, said the far-reaching attack took more than a year and a half to execute and was personally supervised by Zelensky.

The operation saw drones transported in containers carried by trucks deep into Russian territory, he said. Ukraine attacked Russian nuclear-capable long-range bombers at a military base deep in Siberia. 

"Thirty-four per cent of the strategic cruise missile carriers stationed at air bases were hit," Zelensky said.

"Our personnel operated across multiple Russian regions – in three different time zones. And the people who assisted us were withdrawn from Russian territory before the operation, they are now safe." 

The drones reportedly hit 41 planes stationed at several airfields, including A-50, Tu-95 and Tu-22M aircraft, the official said. Moscow has previously used Tupolev Tu-95 and Tu-22 long-range bombers to launch missiles at Ukraine, while A-50s are used to co-ordinate targets and detect air defences and guided missiles.

Russia's Defence Ministry in a statement confirmed the attacks, which spanned five airfields. The FPV drones damaged aircraft and sparked fires on air bases in the Irkutsk region, more than 4000 kilometres (2500 miles) from Ukraine, as well as Russia's northern Murmansk, it said. Strikes were repelled in the Amur region in Russia's Far East and in the western regions of Ivanovo and Ryazan, the ministry said.

Ukraine's President Volodymyr Zelensky and Head of the Security Service of Ukraine Vasyl Maliuk. – Reuters

It is the first time that a Ukrainian drone has been seen in the region, local Governor Igor Kobzev said. He also said in a statement that the drone had been launched from a truck. Russian officials in the Ryazan and Murmansk regions also reported drone activity, but did not give further details.

In his evening address, Zelensky said that 117 drones had been used in the operation. He claimed the operation had been headquartered out of an office next to the local FSB headquarters. The FSB is the Russian intelligence and security service.

The military source said it was an “extremely complex” operation, involving the smuggling of first-person view, or FPV, drones to Russia, where they were then placed in mobile wooden houses.

“Later, drones were hidden under the roofs of these houses while already placed on trucks,” the source said.

"At the right moment, the roofs of the houses were remotely opened, and the drones flew to hit Russian bombers.” 

Social media footage shared by Russian media appeared to show the drones rising from inside containers while other panels lay discarded on the road. One clip appeared to show men climbing onto a truck in an attempt to halt the drones.

USDefense Secretary Pete Hegseth was briefed on Ukraine’s attack Russia during a stop at Nellis Air Force Base and was monitoring the situation. A senior defense official said on the condition of anonymity to discuss sensitive matters that the US was not given notification before the attack. The official said it represented a level of sophistication the US had not seen before.

A drone lifts off from wooden sheds loaded onto a truck at the perimeter of an air base in Irkutsk Region, Russia. – Reuters

The attack came the same day as Zelensky confirmed after days of uncertainty that Ukraine will send a delegation to Istanbul for a new round of direct peace talks with Russia this week.

In a statement on Telegram, Zelensky said that Defence Minister Rustem Umerov will lead the Ukrainian delegation.

“We are doing everything to protect our independence, our state and our people,” Zelensky said.

Ukrainian officials had previously called on the Kremlin to provide a promised memorandum setting out its position on ending the war before the meeting takes place. Moscow had said it would share its memorandum during the talks.

The talks, proposed by Russian President Vladimir Putin, have so far yielded the biggest prisoner exchange of the war – but no sense of any consensus on how to halt the fighting.

US President Donald Trump has demanded Russia and Ukraine make peace and he has threatened to walk away if they do not – potentially pushing responsibility for supporting Ukraine onto the shoulders of European powers – which have far less cash and much smaller stocks of weapons than the United States.

According to Trump envoy Keith Kellogg, the two sides will in Turkey present their respective documents outlining their ideas for peace terms, though it is clear that after three years of intense war, Moscow and Kyiv remain far apart.

In June last year, Putin set out his opening terms for an immediate end to the war – Ukraine must drop its NATO ambitions and withdraw all of its troops from the entirety of the territory of four Ukrainian regions claimed and mostly controlled by Russia.

Ukraine destroys more than 40 military aircraft in drone attack deep inside Russia. – AP

Russia launched the biggest number of drones — 472 — on Ukraine since the full-scale invasion in February 2022, Ukraine’s air force said.

Russian forces also launched seven missiles alongside the barrage of drones, said Yuriy Ignat, head of communications for the air force. Earlier, Ukraine’s army said at least 12 Ukrainian service members were killed and more than 60 were injured in a Russian missile strike on an army training unit.

Ukrainian army commander Mykhailo Drapatyi later submitted his resignation after the attack. He was a respected commander whose leadership saw Ukraine regain land on the eastern front for the first time since Kyiv's 2022 counteroffensive. Drapatyi has been in charge of Ukraine's vast wartime land army since November last year.

"This is a conscious step dictated by my personal sense of responsibility for the tragedy at the 239th training ground, which resulted in the deaths of our soldiers," he wrote on Facebook.

"These are young guys from a training battalion. Most of them were in shelters," Drapatyi wrote.

"They were supposed to study, live, fight – not die. My deepest condolences to the families of the victims and to all those who suffered."

The training unit was located to the rear of the 1,000-kilometre (620-mile) active front line, where Russian reconnaissance and strike drones are able to strike. Ukraine’s forces lack troops and take extra precautions to avoid mass gatherings as the skies across the front line are saturated with Russian drones looking for targets.

Northern pressure

Russia’s Ministry of Defence said that it had taken control of the village of Oleksiivka in Ukraine’s northern Sumy region. Ukrainian authorities in Sumy ordered mandatory evacuations in 11 more settlements as Russian forces make steady gains in the area.

Speaking, Ukraine’s top army chief, Oleksandr Syrskyi, said that Russian forces were focusing their main offensive efforts on Pokrovsk, Toretsk and Lyman in the Donetsk region, as well as the Sumy border area.

Russia said it had advanced deeper into the Sumy region of Ukraine, and open source pro-Ukrainian maps showed Russia took 450 square km of Ukrainian land in May, its fastest monthly advance in at least six months.