Manchester United manager and Labour die hard Sir Alex Ferguson used one of his most famous phrases to attack David Cameron - saying it was "squeaky bum time" for the Tory leader.

With polls still showing all three main parties close together, the football knight told the Daily Mirror: "What was the old Harold Wilson saying- a week is a long time in politics? My god, it must have been a long few days for Cameron."

Continuing the football metaphor, he said: "There he is, coasting along, everyone talking about how it's all over, and suddenly it's like he's been leading the table all season and he's gone four defeats on the trot."

Sir Alex also defended using Mr Cameron's privileged upbringing for political advantage as "fair game".

"How can it be class war to say the guy went to Eton, or that he was part of some dreadful right-wing social club at Oxford?" he said.

"Where you come from does matter you know. His policies are all about helping his own sort."

The manager - whose Manchester side also face a nail-biting finale to the Premier League title race - also used the interview to round on Lib Dem leader Nick Clegg.

Referring to his performance during the TV debates, he said: "I must be honest, I don't see this Clegg thing.

"I mean he was fine, and spoke well enough, but I was no clearer what he was about than I was at the beginning."

Sir Alex described Gordon Brown as "solid and strong", while Mr Cameron "looked really weak under pressure and that is the last thing you want in a prime minister".