Moscow has accused Ukrainian helicopters of crossing the border into Russia and hitting a fuel depot in a city that is one of the Russian military’s main logistics hubs for the war effort.

The unverified claim is the first time Ukraine has been accused of a counter strike on Russian soil since Moscow launched its invasion on February 24.

Footage shows the depot ablaze in the Russian city of Belgorod, some 35km from Ukraine’s northern border, which serves Russian military fighting nearby.

Ukrainian defence ministry spokesman Oleksandr Motuzyanyk said he would neither confirm nor deny a Ukrainian role.

“Ukraine is currently conducting a defensive operation against Russian aggression on the territory of Ukraine, and this does not mean that Ukraine is responsible for every catastrophe on Russia’s territory,” he said.

An image circulated by Russia showing firefighters working to put out the blaze. Photo: Getty

Media organisation Reuters viewed security camera footage from a verified location which showed a flash of light from what appeared to be a missile fired from low altitude followed by an explosion on the ground.

CNN said it had geolocated and verified social media videos showing two helicopters flying over Belgorod but could not confirm whether the helicopters were Ukrainian.

Hours after the reported attack, an eyewitness in Belgorod told Reuters  aircraft were flying overhead and there were continuous explosions from the direction of the border.

“Something is happening. There are planes and constant explosions in the distance.”

Kremlin spokesman Dmitry Peskov said authorities were doing everything possible to reorganise the fuel supply chain and avoid disruption of energy supplies in Belgorod.

He said President Vladimir Putin had been briefed about the incident and the strike could jeopardise Moscow’s peace negotiations with Kyiv.

“Of course this cannot be perceived as creating comfortable conditions for continuing the talks,” Mr Peskov said.

Russian troops pull back

Inside Ukraine, Ukrainian forces have been moving back into territory abandoned by withdrawing Russian troops in the north as peace talks resumed on Friday.

But in the southeast, which Russia now says is the focus of its operation, the Red Cross said it had been barred from bringing aid to the besieged city of Mariupol.

After failing to capture a single major Ukrainian city in five weeks of war, Russia says it is pulling back from northern Ukraine and shifting its focus to the southeast.

Russia has painted its draw-down in the north as a goodwill gesture for peace talks but Ukraine and its allies say the Russian forces have been forced to regroup after taking heavy losses due to poor logistics and tough Ukrainian resistance.

Regional governors in Kyiv and Chernihiv said Russians were pulling out of areas in both those provinces, some heading back across borders to Belarus and Russia.

In Irpin, a commuter suburb northwest of Kyiv that had been one of the main battlegrounds for weeks, now firmly back in Ukrainian hands, volunteers and emergency workers carried the dead on stretchers out of the rubble.

Kyiv regional governor Oleksandr Pavlyuk said Russian forces had also withdrawn from Hostomel, but were still dug in at Bucha, between Hostomel and Irpin.

Further north, Russian forces have withdrawn from the site of the Chernobyl nuclear disaster, although Ukrainian officials said some Russians were still in the radioactive “exclusion zone” around it.

Red Cross rescue plan postponed

Thousands of civilians are trapped in Mariupol which has been under constant shelling. Photo: Getty

The Red Cross has been forced to postpone an attempt to evacuate civilians trapped in the besieged city of Mariupol.

Tens of thousands of people have been unable to escape the city which has been under constant shelling from Russia since the beginning of the invasion.

The International Committee of the Red Cross had planned to bring in three vehicles and create safe passage for a convoy of 54 Ukrainian buses and an unknown number of private vehicles.

However the conditions had made it impossible to proceed.

“The ICRC team that had been on its way to Mariupol on Friday to facilitate the safe passage of civilians had to return to Zaporizhzhia after arrangements and conditions made it impossible to proceed,” the ICRC said.

“They will try again on Saturday to facilitate the safe passage of civilians from Mariupol.

“For the operation to succeed, it is critical that the parties respect the agreements and provide the necessary conditions and security guarantees.

“If and when the safe passage operation does happen, the ICRC’s role as a neutral intermediary would be to accompany the convoy out from Mariupol to another city in Ukraine.”

Mariupol has been encircled since the early days of the Russian invasion of Ukraine that began on February 24.

Previous efforts by aid agencies to secure access have failed. The Mariupol mayor said this week that up to 170,000 residents were trapped there without power and dwindling supplies while the UN human rights team is probing reports of mass graves.

Russian gas still pumping

Russia has allowed gas to keep flowing to Europe despite a deadline for buyers to pay in roubles or be cut off.

An order by President Vladimir Putin cutting off gas buyers unless they pay in roubles from Friday had caused alarm in Europe, where it was seen as Moscow’s strongest card to play to retaliate for Western financial sanctions.

Germany, the biggest buyer, rejected the demand as “blackmail”.
But pipelines were pumping as normal on Friday.

Kremlin spokesperson Dmitry Peskov said the decree would not affect shipments which were already paid for, only becoming an issue when new payments were due in the second half of the month.

“Does this mean that if there is no confirmation in roubles, then gas supplies will be cut off from April 1? No, it doesn’t, and it doesn’t follow from the decree,” Mr Peskov told reporters.

-with AAP