Blair chaired the meeting that led to Kelly naming plan

Tony Blair chaired the decisive meeting at which a change of stance took place over David Kelly, leading to the scientist's identity being disclosed, the most senior civil servant in the Ministry of Defence revealed yesterday.

Sir Kevin Tebbit also dismissed as untrue a number of entries about the affair made in the diaries of Alastair Campbell, the Prime Minister's former director of strategy and communications.

Sir Kevin, the permanent secretary at the MoD, admitted at the Hutton inquiry that he had described Dr Kelly as "weird and rather eccentric" just 24 hours before the scientist's apparent suicide.

He made the remarks to James Robbins, the BBC diplomatic correspondent, at a reception given by the Italian ambassador.

He insisted "they were not intended as a smear", but were jocular asides about Dr Kelly's decision to talk to Andrew Gilligan, defence correspondent for BBC Radio 4's Today programme, who had alleged in a broadcast that the Government sexed up the Iraq arms dossier. Sir Kevin was questioned by Jeremy Gompertz QC, counsel for Dr Kelly's family, about a newspaper report of the conversation, which claimed he had made "a circular motion with his finger around his temple", implying Dr Kelly was mad.

Sir Kevin maintained that was a slur against him, but admitted that he had not complained to the newspaper, let alone taken legal action.

Sir Kevin's appearance to be cross-examined had been delayed by an eye operation. Lord Hutton told the inquiry that his report into the circumstances surrounding the death of Dr Kelly would proabably not be ready before the new year.

Sir Kevin told Lord Hutton that the initial feeling among his colleagues was that there was nothing to be gained by naming Dr Kelly, but then the decision was taken to release a press statement, which started the process by which Dr Kelly was ultimately identified.

Pressed repeatedly by Mr Gompertz on who took the decision, Sir Kevin said: "The change of stance, as you put it, was as a result of a meeting chaired by the Prime Minister. The decision was taken at the meeting in No 10, with which the MoD concurred."

Sir Kevin admitted that no one from the MoD was at the meeting on 8 July, which was attended by the Prime Minister's close advisers. When the Sir Kevin arrived, Mr Blair told him it was over and that he would be briefed by Jonathan Powell, Downing Street's chief of staff.

Sir Kevin denied a claim made by Mr Campbell in his diaries that he and Sir David Omand, No 10's security co- ordinator, had been parties to a discussion on how the scientist's name could be leaked. "I understand that Alastair Campbell has a very racy diary style, but this was never passed on to us," Sir Kevin said.

He also denied another claim in the diaries that he had described Dr Kelly to Mr Campbell as "a show-off". Sir Kevin said: "No, I do not believe I had used those words."

Michael Ancram, the shadow Foreign Secretary, said in a statement after the hearing: "Kevin Tebbit's evidence is yet another damning indictment of Tony Blair's role in the naming of Dr Kelly.

"Sir Kevin has said the key decision on the naming strategy 'was taken at the meeting in Number 10'.

"That meeting was chaired by the Prime Minister. The Prime Minister's denials are now shown to be a sham."