Ukrainian forces conducted large-scale drone strikes on several air bases deep inside Russia, destroying multiple combat planes, Ukrainian Security Service (SBU) said on Sunday.
The operation, named 'Spiderweb', involved the most ambitious simultaneous strikes on Russian air bases since the war started in 2022.
According to an SBU source, over 40 aircraft were known to have been hit, including TU-95 and Tu-22M3 strategic bombers and one of Russia's few remaining A-50 surveillance planes, CNN reported.
According to the SBU, the operation caused an estimated damage of $7 billion and targeted 34 per cent of Russia's strategic cruise missile carriers at its main air bases.
The airfields targeted included Belaya in Irkutsk, some 4,500 kilometres from Ukraine's border with Russia, and the Dyagilevo base in Ryazan in western Russia, about 520 kilometres from Ukraine.
According to the source, the Olenya base near Murmansk in the Arctic Circle was also hit, and the Ivanovo air base was also struck, CNN reported.
Russian Defence Ministry on Sunday confirmed that five air bases were attacked by Ukrainian drones damaging an unspecified number of aircraft.
"Today, the Kyiv regime staged a terror attack with the use of FPV drones on airfields in the Murmansk, Irkutsk, Ivanovo, Ryazan, and Amur Regions. All terror attacks on military airfields in the Ivanovo, Ryazan, and Amur Regions were repelled. No casualties were reported either among servicemen or civilians. Some of those involved in the terror attacks were detained," the Russian Defence Ministry said in a statement.
For the first time it was established that Olenogorsk (Murmansk region) and Sredny (Irkutsk region in Siberia) were attacked from close proximity by using trailer trucks by the attackers.
"As a result of the launch of FPV drones from territories in the close proximity to military airfields in the Murmansk and Irkutsk Regions, several aircraft caught fire. The fires were extinguished," the Russian MoD said.
Ukrainian operation comes as the two warring nations are set to return to peace negotiations on Monday.
The talks, which are set to take place in Istanbul, are facing uncertainty, CNN reported.
Ahead of the fresh negotiations, US Secretary of State Marco Rubio spoke with his Russian counterpart on Monday.
Ukrainian negotiators set to present new proposals to Russian representatives at the second round of direct peace talks in Istanbul on Monday.
Observers in Moscow speculate that Ukrainian President Volodymyr Zelenskyy wants to pressurise Moscow ahead of the talks in Istanbul.
Zelenskyy said on Sunday that Ukrainian armed forces had conducted a 'brilliant operation' in Russia aimed 'exclusively at military targets'.
He said the operation inflicted significant losses on Russia, which he termed as 'justified and deserved'.
In his address to the nation on Sunday, Zelenskyy thanked Ukraine's Security Service and all those involved in the operation and mentioned that 117 drones were used in the operation.
He noted that the preparation of the operation took over a year and a half and mentioned that planning, organisation and every detail were perfectly executed.
He said, "Just now, I received a report from Head of the Security Service of Ukraine, Vasyl Maliuk -- a brilliant operation was carried out. It took place on enemy territory and was aimed exclusively at military targets -- specifically, the equipment used in strikes against Ukraine.
"Russia suffered truly significant losses -- entirely justified and deserved. I thank the Security Service, General Maliuk personally, as well as everyone who was involved in the operation. The preparation took over a year and a half. Planning, organization, and every detail was perfectly executed. I can say with certainty that this is an absolutely unique operation."
"What's most interesting -- and this can now be stated publicly -- is that the 'office' of our operation on Russian territory was located directly next to FSB headquarters in one of their regions. In total, 117 drones were used in the operation -- with a corresponding number of drone operators involved. 34% of the strategic cruise missile carriers stationed at air bases were hit. 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. It is genuinely satisfying when something I authorized a year and six months ago comes to fruition and deprives Russians of over forty units of strategic aviation. We will continue this work," he added.
He said that Ukraine's intelligence, before the operation, indicated that Russia was preparing another massive strike.
He urged people not to ignore the air raid alerts.
"Even before this operation was carried out, we had intelligence indicating that Russia was preparing another massive strike. And it is very important for all our people not to ignore the air raid alerts. Last night, there were nearly 500 Russian drones, attack drones. Each week, they have been increasing the number of units used per strike. Now, they have also prepared Kalibr missiles launched from naval carriers. We know exactly who we are dealing with. And we will defend ourselves by all means available to us - to Ukraine and the Ukrainian people. Not for a single second did we want this war," he said.
The President said that Ukraine offered a ceasefire to Russia.
However, he said that Russia continues to choose the war, even though the US proposal for a full and unconditional ceasefire has been on the table since March 11. He urged international community to pressurise Russia through diplomacy and sanctions.
"We offered the Russians a ceasefire. Since March 11, the US proposal for a full and unconditional ceasefire has been on the table. It was the Russians who chose to continue the war -- even under conditions where the entire world is calling for an end to the killing. And pressure is truly needed - pressure on Russia that should bring it back to reality. Pressure through sanctions. Pressure from our forces. Pressure through diplomacy. All of it must work together," he said.
Meanwhile, Major General Mykhailo Drapatyi, commander of Ukraine's land forces, tendered his resignation on Sunday, taking responsibility for a lethal Russian missile strike on a Ukrainian military training facility that resulted in the deaths of 12 soldiers and injuries to 60 others, according to a Reuters report.
Drapatyi, who has led Ukraine's wartime land army since November last year, expressed deep sorrow over the tragedy at the 239th training ground.
Writing on Facebook, he said, 'These are young guys from a training battalion. Most of them were in shelters. They were supposed to study, live, fight -- not die.'
He extended his deepest condolences to the families of the victims and those affected.
Zelenskyy said that he had called a meeting to examine the incident and would summon senior commanders, including top commander Oleksandr Syrskyi, once Defence Minister Rustem Umerov returns from talks with Russian negotiators in Turkey.
Zelenskyy emphasised the critical need to preserve all frontline personnel, saying, "Every life must be preserved. All decisions needed to do this will be adopted," following a deadly missile strike on a Ukrainian military 'tent camp' in the central Dniepropetrovsk region.
The Russian military confirmed the strike amid rising tensions after the Russian Defence Ministry accused the Kiev regime of coordinated terrorist attacks using FPV drones on multiple Russian airfields.
-- with inputs from PTI