Ken Livingstone has not listed a single donation on the Electoral Commission website since he became Mayor of London eight years ago, prompting Tory accusations that he may be trying to conceal the identity of donors.

As the Mayor of London began his reelection campaign, the commission confirmed that it is investigating whether money given to help his reelection has been declared properly.

Under the law introduced in 2000, donations of more than £1,000 received by political figures must be declared to the commission within 30 days. Boris Johnson, Mr Livingstone’s opponent, has already listed donations of £87,600 on the commission’s website. Mr Livingstone does not list any and does not even have an entry on the website. Labour says that all donations are sought for a Labour Party campaign, which includes the London Assembly elections, rather than for the mayor’s own campaign.

Donations to a party fund, rather than individuals, are subject to less rigorous reporting requirements. They need only be declared above a £5,000 limit and are published every three months rather than after 30 days. There is also no way of identifying

which donations to the party were intended for Mr Livingstone, even if donors say they are sending money for his campaign, meaning, in effect, that donors’ names could be kept secret.

Greg Hands, the Tory MP for Hammersmith & Fulham, called on the Electoral Commission to investigate after reviewing the form requesting donations on the “Back Ken” website. The form asks for money under the heading “Yes, I want to help reelect Ken Livingstone”, and asks that cheques be made payable to the “Ken Livingstone campaign fund”. There is no mention on the form that the money will go anywhere other than Mr Livingstone’s reelection. Furthermore, the document states that it is “printed and promoted” on behalf of Mr Livingstone rather than Labour London. This could be in conflict with rules that say that donations to parties must not specify that they are for a particular candidate.

Electoral Commission guidance issued for the 2008 elections says: “Where a donation is made to a local party fighting fund, this constitutes a donation to the party rather than to the candidate (unless the person giving the donation specifies that it is for the benefit of a particular candidate). If money donated to the fighting fund is then passed on to the candidate or used to fund their campaign, this will constitute a further donation, from the party to the candidate, and should be reported as such.”

Peter Wardle, the chief executive of the Electoral Commission, confirmed at a meeting of the Justice Select Committee yesterday that it was investigating. Andrew Tyrie, a Conservative MP on the committee, said: “If the Labour Party is being used as a conduit to the Livingstone campaign, then this would appear to be a breach of the spirit, if not the letter, of the law.”

A Labour spokesman said: “All fundraising for the mayoral and the GLA campaigns is done by the London Labour Party. Donations in London and the rest of the country are declared to the Electoral Commission in accordance with the rules governing donations to political parties in the usual way. These arrangements have been checked with the Electoral Commission as being entirely appropriate.

“Fundraising is not carried out by Ken Livingstone personally. He is not registered as a receiver of donations. This has been checked and approved by the Electoral Commission.”

At his launch yesterday, Mr Livingstone urged Londoners not to “turn the clock back” as he battled to get his reelection bid back on track. With a poll suggesting that he is trailing behind Mr Johnson, the mayor said that the “stakes are incredibly high”.

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