Scotland Yard has refused to confirm whether a file on Labour peer Baroness Uddin is among those handed to prosecutors yesterday.

The Metropolitan Police say evidence on four parliamentarians was passed to the Crown Prosecution Service on Monday, November 23, and that a small number of cases remain under investigation.

A spokeswoman said the evidence concerned "parliamentary expenses", and added: "The files relate to four people based in the House of Lords and the House of Commons, and will now be subject to CPS consideration of whether there should be any charges."

Police said they were not prepared to discuss those individuals involved.

However, a small number of MPs and peers have been consistently named in media reports on the police investigation into parliamentary expenses.

Among them is Baroness Uddin, who allegedly claimed £100,000 in allowances by registering a flat off Wat Tyler Way, Maidstone, as her main home in order to claim a £30,000-a-year second home allowance on a property in London.