Sir Keir added that Rayner, who grew up in poverty and left school at 16, was “the best social mobility story this country has ever seen”.

Asked whether he missed her, he was quoted as saying: “Yes, of course I do. I was really sad that we lost her.”

Pressed on whether she would be back in the cabinet, he replied: “Yes. She’s hugely talented.”

The reported comments are more categorical than previous remarks he has made about Rayner, who was also deputy Labour leader and housing secretary.

At a G20 summit last month, Sir Keir told broadcasters he “absolutely” wanted to see her make a return to government “at some stage”.

Rayner has been replaced as deputy Labour leader by Lucy Powell, another former cabinet minister, following an election among party members.