Tooting MP Sadiq Khan was today made shadow secretary of state for transport in a “bitter-sweet” promotion after clinging on to his seat last week.

In an exclusive interview with the Wandsworth Guardian, he revealed Harriet Harman telephoned this afternoon to make him the offer.

Mr Khan won Tooting by a margin of 2,524 votes but lost his position as minister of state for transport when Labour finally surrendered their power last week.

He said: “It’s obviously bitter-sweet, because we’re now the wing Government. But it’s important that we hit the ground running.

“What I’m not going to do is get delusions of grandeur and forget where I came from,” he added.

“One thing that worries me is that I see MPs in Parliament who, once they climb up the greasy pole, they lose touch with their communities.

“I don’t ever want that to happen. I’m very humbled that I was returned on May 6, and I want to carry on doing what I was doing.”

Mr Khan was made Britain’s first Muslim cabinet minister last year, second only in the Department ofor Transport to Lord Adonis - who has now stepped down.

He pledged to help fight any cuts in Tooting, especially to schools and the refurbishment of Earlsfield station.

Nationally, he said his priorities included improving high-speed rail transport and Crossrail.

But despite his loyalty to the party, Mr Khan said he was glad former Prime Minister Gordon Brown had abandoned a coalition deal with the Liberal Democrats.

He said: “Although no party won the election, it was quite clear the Labour party lost the election. I think what would have been arrogant for us to do was to try and stay in Government with a coalition with the Liberals.

“It would have been a disaster. It would have been a weak Government and it would have been a slap in the face for all of the those people who live in the constituencies that voted the Conservatives in. We have to accept that although the Conservatives didn’t win, we lost.”