Vince Cable faces probe over Nick Clegg poll

Business Secretary Vince Cable is facing a probe into whether a controversial poll seen as a bid to undermine Nick Clegg's leadership should have been declared as a gift.

Mr Cable's close friend Lord Oakeshott commissioned research into the Liberal Democrats' prospects in a series of key constituencies.

The findings - which suggested seats could be lost unless there was a change of leader - were then leaked in the wake of dire local and European election results last month.

Mr Cable has admitted that he knew polling was being carried out in his Twickenham constituency, but denied involvement in surveys in Mr Clegg's Sheffield Hallam seat or that of Danny Alexander, Chief Secretary to the Treasury.

Lord Oakeshott resigned from the party after being publicly condemned by the Business Secretary.

A spokeswoman for parliamentary standards commissioner Kathryn Hudson confirmed she had launched an investigation into whether Mr Cable and Wells MP Tessa Munt should have declared the polling in the register of members' financial interests.

Under Commons rules, any benefits worth more than £1,500 in a calendar year should be reported.

Mr Cable said in a statement: "It is right that any concerns raised by a member of the public sho