HE HAS been described as the best Prime Minister we never had. Sitting in his modest office in Southampton, John Denham threw back his head and laughed heartily at the suggestion.

"They never said it to me!" he grinned, the laughter lines around his eyes deepening.

But before his dramatic resignation as Home Office minister, MP John Denham was tipped for the top.

He had risen through the political ranks from Southampton city councillor to high profile government minister.

He had held down posts at the Department of Health, Department of Social Security and the Home Office as well as becoming Minister for Children and Young People.

So it was an unusual and, some would say, courageous career move when he quit the front bench in 2003 over the Iraq War.

Since then the MP for Southampton Itchen has refused to fade into obscurity.

His prominent position as leader of the watchdog that scrutinises the Home Office - one of the biggest and most troubled government departments - has fuelled speculation about his political ambitions.

"If an opportunity came up where I could go back as a minister in a position where I felt I could make a difference I certainly wouldn't rule that out," he said.

But he is aware there are no guarantees.

"I do recognise that if you leave the government under those circumstances you've got no right to expect to come back.

"So I've spent the last two or three years getting on with my job and not calculating what I say on whether it's going to get me back into office or not.

"If I'd tried to keep my nose clean and not say something that might upset somebody, I would have been less a effective MP."

Perhaps when Gordon Brown steps into power Denham could be back at the Home Office - as leader.

"I don't know," he says, smiling.

"We'll just have to wait and see and otherwise get on with the day job."