Sir Donald Acheson, the former chief medical officer, defended his actions during the early years of the BSE crisis. He attacked the former chief veterinary officer, Keith Meldrum, for comments Mr Meldrum made during a meeting with leaders of the farming industry in June 1988.
But Sir Donald later admitted errors he also made in trying to calm public fears in 1990.
Mr Meldrum had told the 1988 meeting with farmers that Sir Donald "advised that no immediate action was called for" to deal with the problem.
But when it was put to Sir Donald at the BSE inquiry in London yesterday that he had felt no cause for concern 10 years ago, he replied that it was "absolutely not the case".
He said that the Ministry of Agriculture had already sent him a letter in March 1988, about BSE-infected cattle.
Of Mr Meldrum's comments, he said: "That is quite inconsistent with what my actions were when I got the letter. It was also quite inconsistent with the minute put out to ministers following a meeting on 17 March 1988."
Sir Donald added that the subject of that meeting with various experts in the field had been to get them to "address the worst case scenarios".
Despite his criticism of Mr Meldrum, Sir Donald admitted using the wrong words in a press statement he issued aimed at reassuring the public of the safety of British beef.
He told a news conference on 16 May 1990: "There is no risk associated with eating British beef."
He also said that everyone, including children and hospital patients, "can be quite confident" with the safety of it.
But at the inquiry yesterday he revealed that his statement should have read that "there is no scientific justification for not eating British beef". He said: "Instead of saying no scientific justification, I said no risk. I should not have done that because the advice from my groups [experts] was that there was a remote risk and not no risk."
Sir Donald expressed concern that the ministry had allowed a six-month delay to develop before passing on information to him about the BSE epidemic. He also criticised the "incessant" cutbacks and reviews being carried out on the Civil Service during his time as chief medical officer.