The appeal by the Formula One chief executive, Mr Bernie Ecclestone, to the standards watchdog to reverse his ruling and let Labour keep his £1 million gift was turned down last night.
Sir Patrick Neill acted to crush any lingering prospects of Labour holding on to the donation made to the party five months before the election.
Meanwhile, the EU Commissioner, Mr Padraig Flynn, rejected the British government's suggestion that Europe would lose the sport to the Far East if cigarette promotion on cars is banned.
Mr Flynn urged Britain to change its mind and negotiate for a "more acceptable" solution to the EU's plans for a total tobacco advertising ban at talks in Brussels on December 4th.
The move by Sir Patrick, the chairman of the committee on standards in public life, who advised Labour to return the money on Monday, came just hours after his office said it was "very unlikely" he would respond yesterday to the plea by Mr Ecclestone to let Mr Tony Blair's party keep his gift.
A spokesman for Sir Patrick said last night: "The chairman has no intention of changing his advice. He will, however, be considering Bernie Ecclestone's letter over the weekend."
The gift matched the largest donation by an individual to Labour and its loss represented a major blow to a party currently £4.5 million in debt.
Sir Patrick conceded in offering his advice on Monday that Labour had done nothing wrong in accepting the gift but he urged the party to return it, in light of the controversy over Formula One's subsequent exemption from a planned tobacco company sponsorship ban.
The day began with Mr Ecclestone breaking what had been a period of relative silence with an interview in the Mirror newspaper and a letter in the Times explaining his position more clearly than at any stage so far in the episode.
In his Times letter, he questioned the ability of any major donor to contribute to political parties in the light of the advice to return the £1 million gift on Monday.
"Sir Patrick Neill's recommendation to the Labour Party that it repay my only donation to the party is well-intentioned but wrong unless Conservatives and Labour both now repay all donations from anyone who might appear to have benefited from government decisions," he said.
Before Sir Patrick's intervention last night, an official in his office said he would consider the request, though he could not predict the outcome.
The official from the committee on standards in public life made plain that Sir Patrick's advice did not apply to donations from other sources.
It was sui generis - a response to a unique situation and should not prejudice any other funding situations.
Ministers from across the EU are due to meet on December 4th to try to agree a directive on tobacco advertising.
Mr Flynn warned the British Public Health Minister, Ms Tessa Jowell, in a telephone call last week that the government's change of heart on Formula One threatened to ruin efforts to agree a comprehensive ban after years of trying.
Now, in a letter to Ms Jowell, he says he is disappointed that the offer of an effective 4 1/2-year transition period before the ending of sports sponsorship would come into force is not deemed sufficient.
Mr Flynn says in the letter: "I believe that the implicit threat that the industry would relocate more grand prix events outside the EU is not credible."
Nor would television retransmission of grand prix events taking place in countries with no tobacco advertising restrictions undermine the EU's anti-smoking efforts, the Commissioner claimed.
Calling on the government to change its mind, Mr Flynn told Ms Jowell: "If we fail to reach agreement, I will be in a very difficult position in defending the proposal against demands for its withdrawal."
But last night on Channel 4 News, Minister Without Portfolio, Mr Peter Mandelson, said it was Mr Flynn who had changed his approach and accepted that an extended phasing-out period might be required.
"I'm very glad Mr Flynn has reflected on this policy.
"He has moved a long way in recognising the strength of the case made by the British government and other EU countries in saying this is simply not something that can be achieved overnight or by waving a magic wand and producing alternative sources of sponsorship for this industry."