Whitehall accused of Iraq probe cover-up

Carne Ross, who quit the Foreign Office in 2004 after criticising Britain's involvement in the war, said he had been denied access to key material ahead of his recent appearance.

Britain's former Iraq expert at the United Nations also claimed he was subjected to "subtle intimidation" from Whitehall to drop references to a classified memo.

Giving evidence to Sir John Chilcot's panel earlier this month, Mr Ross complained about a "culture of unaccountability and, sometimes, dishonesty" in Government.

He said his experience of giving evidence had convinced him there was "an emerging and dangerous problem with the process". And he renewed a call for all but a few of the "most secret" documents related to the invasion to be made public.

"Though profoundly embarrassing, there is little here that damages national security, except in the hysterical assessment of officials protecting their own reputation," he said.

Mr Ross said "most" of the key documents he had requested to see were missing from large files sent to him to look through before his inquiry appearance.

He was told certain records, including those related to a visit to Syria by the then prime minister Tony Blair, could not be found – something he said was "simply not plausible".

He said the inquiry was being given a "very one-sided account" that military action was "more or less unavoidable" because sanctions and containment were failing. "The true story is there to be seen in the documents.

"In memos, submissions to ministers and telegrams, the official view is very clear – while there was concern at the erosion of sanctions, containment had prevented Iraq from rearmament."

A spokesman for the inquiry said it was satisfied it was being supplied with all the necessary documentation and that Mr Ross, in spite of being asked four weeks in advance, had not notified the inquiry of any documents he wished to have declassified so he could refer to them.