Viral videos have emerged of Ukrainian farmers towing away tanks that have run out of fuel or been abandoned by Russian troops.

It is understood that Russia will also be unable to restock with Kh-55 cruise missiles, which are launched from the air and can carry nuclear warheads, because they rely on imported components.

The Kh-55 is used by Russia, China and Iran, and uses an engine manufactured in Kharkiv, senior defence sources told The Telegraph.

All Russian missiles launched from helicopters and ships use Ukrainian-manufactured engines.

Western sanctions mean Putin is also unable to buy arms from France, which has supplied hundreds of millions of pounds worth of equipment to Russia since the invasion of Crimea in 2014.

Sources said the current stock levels of the Russian military were “pretty bad”, following Mr Putin’s inability to capture Ukraine as quickly as many analysts had expected.

‘Donor conference’

Volodymyr Zelensky, the Ukrainian president, has asked Western nations to continue to supply his forces with “lethal aid”, including missiles and other arms to be used against Russian forces.

On Thursday, Ben Wallace, the Defence Secretary, convened a “donor conference” of 35 countries to persuade them to give more arms to Mr Zelensky’s troops.

So far, the UK has supplied 4,000 next-generation anti-tank weapons (NLAWs) and Javelin anti-tank systems and pledged to send Starstreak air defence systems and 6,000 new anti-tank and high explosive missiles. 

Britain has also sent Ukraine body armour, helmets, boots, ration packs and communications equipment.