GORDON Brown was not up to the job of being Prime Minister and knew it, according to Jack Straw, the former Cabinet Minister who ran his leadership campaign in 2007.

The ex-Foreign Secretary said he and other colleagues, including Harriet Harman, now the deputy Labour leader, David Miliband, the former Foreign Secretary, and Alan Johnson, who was Home Secretary, considered challenging Mr Brown but were "afraid to strike", believing it could make Labour's plight even worse.

The Blackburn MP revealed how Cabinet colleagues talked about challenging their leader all the time.

He said: "The tragedy was we realised – but so did Gordon – that this job, for which he'd become obsessed and devoted his life to, was a job he couldn't properly do. He just lacked the fundamental qualities to do it.

"Of course, I thought about whether I should stand at various moments. So did others; David Miliband, Alan Johnson. I talked to them. I talked to Harriet Harman.

"If you say we were ready to wound but afraid to strike, that's true. We backed off because although the situation was desperate we were never certain we wouldn't make it worse."

Pressed about the qualities Mr Brown was lacking, Mr Straw said: "He didn't understand that if you're Prime Minister, you're faced with decisions which come in the door and the window all the time and that wasn't the case when he was running the British economy, where he had four big sets of decisions to make a year.

"He didn't properly understand the importance of how you bring together a team."

The backbencher explained how the former premier had some "very, very talented, thoroughly decent people" in his team yet he also always employed others, who were "skilled in the dark arts and that undermined trust in him and his trust in others".

In his newly published memoirs, the former Secretary of State says Tony Blair encouraged him to stand for the Labour leadership, which would have meant standing against Mr Brown. Mr Straw said: "I could have been Prime Minister and a reasonably effective Prime Minister. I thought about it. I would have been able to run government pretty well. The question was, did I want it enough? Others wanted it much more."