The former President, who delighted Labour activists at the conference four years ago, has been brought back to help an embattled Labour Party at what is fast becoming a “transition” conference.

Mr Clinton, who has known Mr Brown longer than he has Mr Blair, said that he had been a great Chancellor and would be a good prime minister. He also strongly praised Mr Blair’s record.

In an interview in The Spectator this week Mr Clinton showed that he is keeping abreast of political developments in Britain.

He said of Mr Blair and Mr Brown: “I just want them to stay together, to decide what to do and keep the Labour Party together. The political difficulties of the moment should not obscure for the British people the fact that this Government has been good for their country.”

He added: “You’ve got a great economy, better growth than America has and less inequality than America. Gordon Brown has been a great Chancellor of the Exchequer. They just have to work this out. You can make too much of the politics and too little of the substance. The point is that new Labour has served the British people well.”

Asked whether Mr Brown would be a worthy prime minister, Mr Clinton replied: “There’s no doubt. I have known him since 1990 and I think he’d be a good prime minister.” Mr Clinton, then Governor of Arkansas, first met Mr Brown at the Bilderberg conference in the Black Forest resort of Baden-Baden.

Times Recommends

• Revealed: how Eurocrat leaked secrets over dinners
• Politicians use the net to brainstorm
• British spy in longbow plot to kill Himmler