Asked how bad the situation on the ground is [in Mariupol], Mr Clarke said: ‘It’s difficult to exaggerate how completely devastated the city is. There is not a single building that is either unburnt or unbroken.

“The people are just traumatised and dazed. They are living without electricity or food or heat. The temperature’s recently risen but it has been sub-zero temperatures until last week.

“The fires are still burning, people have been cooking on wood fires outside their bomb shelters or in their bomb shelters.

“There are no shops, no banks, no provisions. Everything that hasn’t burned down has been looted and anyone who can leave has left.