Former Home Secretary David Blunkett told the head of the Prison Service to "machine gun" rioting inmates in a bid to regain control of a jail, it has been claimed.
Martin Narey, then director general, claimed a "hysterical" Mr Blunkett told him he did not care about loss of life after Lincoln jail was taken over by prisoners in October 2002.
Mr Blunkett denied the account of the telephone conversation, saying that the call would have been monitored by his private office.
Writing in The Times newspaper, Mr Narey said he had told Mr Blunkett he would not rush into ordering staff back into the jail if it put lives at risk.
He went on: "He shrieked at me that he didn't care about lives, told me to call in the Army and 'machine gun' the prisoners and - still shrieking - again ordered me to take the prison back immediately.
"I refused. David hung up."
Mr Narey acknowledged that the comments were not meant literally, saying "he surely cannot have intended us to take (them) seriously".
But he said the incident demonstrated that when Mr Blunkett was under pressure "he could be almost impossible to work with".
"I found him always unpredictable and inclined to rush to a decision sometimes on the basis of what had been read to him that morning from the tabloid press," he added.
Mr Narey's article was written in response to Mr Blunkett's newly-published diaries, in which he accuses the then Director General of dithering over the response to the rioters.
