The BBC has refused to back down in its row with the government over reports that Downing Street "sexed up" a dossier on Iraq's weapons of mass destruction.

With senior MPs passing their verdict on the government's evidence later this morning, the BBC governors met last night to agree that it was in the public interest to broadcast the claims.

"We are wholly satisfied that BBC journalists and their managers sought to maintain impartiality and accuracy during this episode," the governors concluded.

With members of the foreign affairs select committee are expected to clear Downing Street spin chief Alastair Campbell of claims that he distorted the Iraq intelligence dossier, Number 10 said last night it still expected an apology from the BBC.

"The BBC should make an immediate apology. If they try to be silly, we will pursue it further," a senior source told today's Times.

On Sunday, the prime minister described claims that the government had altered the now infamous document as being "as serious an attack on my integrity as there could possibly be".

He told the Observer newspaper: "You could not make a more serious charge against a prime minister; that I ordered our troops into conflict on the basis of intelligence evidence that I falsified. The charge happens to be wrong."

Interviewed in today's Guardian, Robin Cook accuses Campbell of using the dispute with the BBC to distract attention away from the claim there was no evidence that Iraq possessed weapons of mass destruction.