He may have apologised for the inflammatory campaign against his rival for the leadership of the Liberal Democrats but Chris Huhne insisted yesterday that Nick Clegg had left "too many loose ends" in his political vision to carry the party into a new era of reinvigorated three-party politics.
Mr Huhne reiterated his regret over the "Calamity Clegg" slogan which appeared on leaflets written by his staff, but said he stood firmly by his message that the younger contender had "flip-flopped" on policies.
"I have made it very clear that there will be no repetition of that in the campaign," he said. "Unfortunately it was a mixture of responsibilities. It was an over-zealous young researcher who was responsible for drawing up the document."
The researcher was not on his staff, he said, denying that, as a former journalist he might have been expected to read what was put out in his name before it was put out. "It was at high speed, on Blackberries; it's not always easy to appreciate the full implications," said Mr Huhne, the party's environment spokesman.
"I was as shocked as anyone... You can't keep tabs on running a big campaign. One thing I have learnt in running an organisation is you have to delegate and trust people."
Mr Huhne ran through the charge sheet against the party's home affairs spokesman, alleging that he had frequently changed his mind in the heat of battle on subjects such as giving priority to proportional representation in a hung parliament, which he appeared not to underline before, and rejection of Continental social insurance for health care, which Mr Clegg had earlier appeared to support.
"I am afraid we do have an issue of trying to communicate as clearly, as forcefully our policies as we can," Mr Huhne said. "Not leaving so many loose ends that we can be attacked on them."
He added: "It's very important that whoever is leader is aware of the need to put forward an extremely clear view, particularly on an area as sensitive as public services."
The row over the Huhne campaign document at the weekend reinforced the impression that the leadership contest has descended into "nasty" politics. Despite refusing to be drawn into a personal slanging match when they went head-to-head on the BBC's Question Time, the Huhne camp's "Calamity Clegg" allegations provoked a furious exchange on The Politics Show.
Critics say Mr Huhne has made his own policy shift in the campaign in favour of unilateral nuclear disarmament, a charge he vehemently denies. When interviewed by The Independent at the start of the campaign, he was asked why he did not say he would go unilateralist. He replied: "We obviously do not put forward policies for the hell of being different. They have to be sensible and sound. Our voters expect us to be rational. You will not find me or Nick streaking down the high streets of Britain like la Cicciolina, the Italian Radical porn star."
Clothed or not, that appears to be what he is doing. He would prefer to replace Trident with a smaller and cheaper arsenal of nuclear-tipped cruise missiles, but if the international talks in 2010 on disarmament gowell, he would be prepared to scrap nuclear weapons without a replacement. "We need at that point either to say no deterrent or to say let's go for a minimum deterrent," he said.