Johnson '100% honest' over donation

The Health Secretary mounted a bullish defence despite the revelation that his Labour deputy leadership campaign had accepted over £3,000 from a "proxy" donor.

He said his team had done "what the law asked us to do" and more to check the source of the cash, which was handed over by immigrant Waseem Siddiqui on behalf of his brother.

"I'm as surprised as anybody," Mr Johnson said. "But all I can say is that we have followed absolutely the procedures."

Ministers rushed to bolster their colleague, while the Tories signalled they were largely satisfied with his explanation - although there is still confusion over whether four donations, including Mr Siddiqui's, were notified to the Electoral Commission on time.

However, the furore is yet another bitter blow for Gordon Brown as he struggles to shift the agenda away from Labour's funding nightmares and back on to policy.

Anti-sleaze laws demand that donations must be transparent and their real source identified.

Waseem Siddiqui gave £3,334 to Mr Johnson's campaign in May last year. However, the 50-year-old told the Sunday Mirror he did not even know who the Health Secretary was. Instead, Mr Siddiqui's brother-in-law Ahmed Yar Mohammed - treasurer of Croydon Central Labour Party - asked him to write a cheque, and then gave him the money.

Mr Mohammed confirmed that he used his brother-in-law to channel the cash, but insisted there had been no intention to conceal the source.

"As a longstanding Labour Party member I wanted to show my support for Alan Johnson by making a contribution to his deputy leadership election campaign," he said in a statement. "As I was travelling at the time, I asked my brother-in-law Mr Waseem Siddiqui to write a cheque for Mr Alan Johnson's campaign. As family members we share a number of financial arrangements. I did this in good faith and at no point was it my intention to disguise my donation."