Ms Truss said: “Well, you are absolutely right about the dire situation, and the United Kingdom has sent teams to the border to assist, particularly in Poland, but also in other countries facing those issues.

“I was in Geneva… the day before yesterday, meeting the UN and others to talk about making sure a humanitarian corridor is established for the safe passage of aid and humanitarian support.”

Vadym Prystaiko, the Ukrainian ambassador to the UK, suggested earlier this week that Ukraine’s military may have to take over control of food supply as the war intensifies.

Speaking during a parliamentary committee, he said problems were already being seen with Ukrainians getting access to cash in some parts of the country.