The Electoral Commission said today that it had referred the controversy over donations to Peter Hain's deputy leadership campaign to Scotland Yard.

In a statement, the elections watchdog said it would be up to the Metropolitan Police to decide whether to investigate.

The move followed a "thorough review'' of more than £103,000 belatedly declared to the Electoral Commission, it said.

"On 29 November 2007, Peter Hain MP informed the Electoral Commission that he had not fully reported to the Commission donations he had received for his Labour Party deputy leadership campaign,'' the Commission said.

"Mr Hain has since met with the Commission and provided additional information about donations he received. The Electoral Commission has undertaken a thorough review of this information.

"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.''