Russia could try to starve Ukrainian cities of food to break the fierce resistance to the invasion, Kyiv’s ambassador to the UK has told MPs.

Vadym Prystaiko said Vladimir Putin is facing a “lack of progress”. with civilians meeting his tanks by hurling “Molotov cocktails from their cars” rather than the “flowers” he dreamed of.

The diplomat warned that the Russian president could “try to crush the will of the Ukrainian people to resist”, and raised concerns about people running out of cash.

There is currently a “lifeline” to secure food supply, but Mr Prystaiko warned of a “bottleneck, a very serious one” and raised the need to explore the option of humanitarian ships being able to arrive in the Black Sea.

Conservative MP Bob Seely asked the ambassador during an appearance before the Commons Foreign Affairs Committee whether the Kremlin’s strategy could be to starve civilians into surrender.

Mr Prystaiko replied: “The support and resilience is going so much against his (Mr Putin’s) plans and in Russia themselves start asking questions, ‘What are we doing?’

“I believe they might use the tactics you described in the second part – try to block our cities, try to soften political position, try maybe some riots in Ukraine, because of the lack of foods, against the government.”

Mr Prystaiko said officials might have to “come up with some military solution to the distribution of food”.

Mr Seely said he recognises that to prevent a civil breakdown “you need arms and you need food”.

The Ukrainian ambassador seemed to hold out little hope over the negotiations between Kyiv and Moscow, saying “we just stated our positions and went back to our capitals”, with the Kremlin wanting demilitarisation and recognition of annexed state Crimea as Russian territory.

Addressing how Mr Putin’s assault can be overcome, Mr Prystaiko said: “The only soft spot he still has is his own population. The circle around him, we don’t believe that they are self-sufficient or risky enough to tell him no.”