British minister Peter Hain has resigned from his post as Work and Pensions secretary after it emerged his failure to declare £103,000 (€135,500) in donations to his campaign to become deputy leader of the Labour Party last year has been referred to police.
Mr Hain said he was leaving his post to clear his name after electoral authorities referred questions over campaign funding to the police.
Former Northern Ireland Secretary Peter Hain
The former Northern Ireland secretary has denied any wrongdoing despite the late declaration of donations for his campaign last year to be elected deputy leader of the ruling Labour Party.
"In view of the Electoral Commission decision today, I will be resigning to clear my name," Mr Hain, who first came to public attention in the 1970s as an anti-apartheid campaigner, said in a statement.
Gordon Brown's office said the prime minister had accepted Mr Hain's resignation.
Mr Brown enjoyed a double-digit lead over the opposition Conservative Party in the first few months of his premiership but it has turned into an equally large deficit following a crisis over mortgage lender Northern Rock, administrative blunders and signs of a faltering economy.
His premiership has already been dogged by a party funding scandal. Labour's general-secretary resigned and police were called in to investigate last year after it emerged a property developer had given more than £600,000 to the party through go-betweens in an apparent violation of electoral law.
An investigation into Mr Hain's campaign funding would only add to an aura of sleaze surrounding the party.
"Following discussions with the Metropolitan Police Service and the Crown Prosecution Service, the Electoral Commission has now referred matters to the Metropolitan Police for them to consider whether an investigation should commence," the commission said in a statement on Mr Hain's case.
Police said they had received the file and that investigations would now begin. "We have received a referral today from the Electoral Commission in connection with potential breaches of the Political Parties Elections and Referendums Act 2000 regarding donations received," a spokeswoman said.
"An investigation will now begin by detectives from the Specialist and Economic Crime Command led by Acting Commander Nigel Mawer." Government colleagues leapt to Mr Hain's defence.
"I am really sad. Peter is an excellent secretary of state. I have worked with him for many years," Health Secretary Alan Johnson told BBCradio when he was told live on air of the resignation. The opposition Conservatives said the resignation was inevitable.
"What is important now is for Gordon Brown to take rapid action to restore effective leadership to a department that has clearly been distracted by the events of the last few weeks," work and pensions spokesman Chris Grayling said.