Hoon -- whose job is on the line for his role in the worst crisis of Blair's six-year premiership -- said to avoid allegations of a cover-up, he overruled top-level advice that he protect the scientist from the public glare.

Widely seen as a potential government "fall guy," Hoon was the most senior official yet to take the stand at the inquiry into the circumstances surrounding the death of David Kelly, who was found with a slashed wrist last month.

Blair is due to testify today and will now face serious probing into his personal role.

Hoon told the inquiry he believed shielding Kelly was not an option after the scientist admitted briefing a BBC reporter who accused the government of "sexing up" a dossier on Iraqi weapons to make the case for a war most Britons opposed.

"I was certainly aware that the prime minister took essentially the same view that I did," he told the inquiry, citing a message from Blair's chief of staff.

"I accept ultimately this was my decision," he added. "I am not in any way trying to avoid that."

At Hoon's prompting, the mild-mannered scientist was grilled by a parliamentary committee on July 15 over his unauthorized meeting with a BBC journalist. Days after the sometimes hostile session, Kelly was found dead at a beauty spot near his home.

Kelly's death, and the failure after the war to find any Iraqi weapons of mass destruction to back up warnings in the dossier, have sent Blair's trust ratings plummeting.

A poll in the Sunday Telegraph showed 67 percent of those questioned thought his government had deceived the public.