Michel Garretta, former head of the national blood transfusion service, agreed that he had failed to take appropriate action after being warned of the high risk of contamination in 1985. He said he was not the only one at fault.
He told the court in Paris: 'I understand very well I made a mistake. I failed to import heat-treated blood.' Mr Garretta and three colleagues are charged with fraud and negligence.
They are accused of distributing unscreened blood products that they knew could be infectious and failing to authorise a US disinfection procedure until a French method had come on to the market. About 1,500 people contracted HIV as a result and more than 250 have since died.