Miliband 'won't run for leadership'

Mr Miliband insisted he was "not a candidate" in the race, and the Chancellor was an "excellent Prime Minister in waiting".

The Cabinet minister's allies have also reportedly told the BBC that he definitely will not stand, despite intense pressure from Blairites.

Mr Milband said: "I've not wavered in my view over the last three years and I'm not wavering now.

"I've meant what I said, I am not a candidate, we've got an excellent prime minister in waiting in Gordon Brown."

He told the BBC: "I'm getting on with my job as Environment Secretary which I think is one of the most pressing issues that we face."

Mr Blair repeatedly refused to answer questions on potential successors at his monthly press conference in Downing Street on Tuesday.