David Cameron says it "is not a matter for me" whether Michael Ashcroft, the Conservative Party's billionaire deputy chairman, pays any tax in the UK.
The Tory leader insisted that Lord Ashcroft's tax affairs are a private matter. But a different rule is now applied by Mr Cameron to Conservative MPs and parliamentary candidates. Anyone who wants a Tory seat in the House of Commons has to be a UK taxpayer, Mr Cameron said.
Lord Ashcroft, who has donated an estimated £5m to the Conservatives and is in charge of their strategy for winning marginal seats, was granted his peerage in 2000, after being nominated by William Hague, when he was the Tory leader.
The Honours Scrutiny Committee, which had a veto over life peerages at the time, attached a unique condition that "to meet the requirements for a working peer, Mr Michael Ashcroft has given his clear and unequivocal assurance that he will take up personal residence in the United Kingdom again before the end of the calendar year".
The peer has told his colleagues in the Tory leadership that he is meeting those conditions he promised to meet nine years ago. But yesterday Mr Cameron would only tell the BBC's Politics Show: "Lord Ashcroft's tax status is a matter between him and the Inland Revenue. What I can say and what he has said is that the undertakings he gave at the time of being made a peer are undertakings that he is meeting." Last week, Mr Cameron was embarrassed by the revelation that one of his leading political allies, Zac Goldsmith, has substantial inherited wealth held in overseas trusts, though he pays tax on his UK income. His London home and Devon farm are owned by trusts based in the Cayman Islands.
Mr Goldsmith is the Tory candidate for Richmond Park, and a leading adviser to Mr Cameron on environmental issues. He promised to end his non-dom status once it was made public.
"In the House of Commons which is responsible for tax, responsible for the economy, I want everyone to be a UK taxpayer in full, no questions," Mr Cameron said. "I think it's important that every candidate who's standing at this election does that, and that's what's happening in Zac Goldsmith's case. I think Zac Goldsmith has done the right thing. I understand that he's backdating it to this year and that's absolutely right as well."
But when pressed on whether the same rule should apply to Lord Ashcroft, Mr Cameron answered: "I'm not responsible for everybody's tax payments. It is a matter between them and the Revenue and I think I've made the position very clear."
Labour MPs have long pressed Michael Ashcroft to say if he is a UK taxpayer and has a vote in the UK. In the House of Lords' annual report on peers' expenses for the year 2003-04, his main residence is recorded as being in Belize, in Central America. In other years, there is no official record of where he was living. Unlike many other peers, Lord Ashcroft did not claim expenses for overnight stays in London or for travelling to and from his main residence, and therefore there is no need for him to tell the Lords authorities where his main residence is.
The House of Lords Appointments Commission says that it does not know whether Lord Ashcroft is UK resident. The Cabinet Office and HM Customs and Revenue have declined to answer questions about his status, on grounds of privacy. Last week, the Conservative Party chairman, Eric Pickles, suggested that Lord Ashcroft is prepared to break his silence on the issue, and would be "happy" to be interviewed on Radio 4's Today programme to discuss his tax status.