The row over the government's evidence of Iraqi weapons of mass destruction rages on, but what is it all about? BBC News Online explains.
How did this row start?
Amid the fevered speculation in the build-up to war in Iraq, the government last September produced its long-awaited dossier of evidence about Iraq's weapons of mass destruction.
Among its claims - as highlighted in Mr Blair's foreword - was that Saddam Hussein's "military planning allows for some of the weapons of mass destruction to be ready within 45 minutes of an order to use them".
A senior official said to have been involved in drawing up the dossier told BBC Radio 4's Today programme defence correspondent Andrew Gilligan that the document was rewritten at the behest of Downing Street to make it "sexier".
The source said the 45 minutes claim was a "classic example" of how uncorroborated evidence was given undue prominence - especially as it came from only one source.
He said: "That information wasn't in the original draft. It was included in the dossier against our wishes because it wasn't reliable."
Mr Gilligan says three other people "in or connected with the intelligence community" have voiced concern to him over the past six months about misuse of intelligence material by Downing Street.
Why did these claims matter?
Tony Blair's justification for going to war with Iraq was the threat posed by Saddam Hussein's weapons of mass destruction.
What was the government's reaction to the BBC story?
Number 10 itself said "not one word of the dossier was not entirely the work of the intelligence agencies".
Tony Blair said it was "absurd" to claim that Downing Street had pressured the security services to "invent" evidence.
Critics say the government is missing the point - that some evidence was hyped up or highlighted more than it should have been.
A succession of ministers have denied this was the case and Tony Blair's communications director Alastair Campbell is demanding an apology from the BBC over the claims.
What have the intelligence services had to say?
John Scarlett, head of the Joint Intelligence Committee, which oversees security service reports for the government, has apparently let it be known he had no bust up with Downing Street over the dossier.
Other unnamed sources have backed up the claims made in the original BBC report.
Does the BBC stand by its report?
Yes. The BBC's director of news, Richard Sambrook, says that the decision to report the source's claim was perfectly proper.
He has accused Mr Campbell of pursuing a vendetta against Mr Gilligan, and of asking for apologies for allegations that were never made.
In his 12 page letter to Mr Campbell he added that the BBC would express regret and tell its audiences if the information provided by its source proved to incorrect. "As we stand today, that is simply not the case," said Sambrook.
So who'll decide who's right?
Two parliamentary select committees investigated the weapons evidence.
MPs on the Commons foreign affairs select committee conducted most of their questioning in public.
They quizzed Mr Campbell and Mr Gilligan, Foreign Secretary Jack Straw, plus anti-war ex-ministers Robin Cook and Clare Short.
The other inquiry is by the Intelligence and Security Committee, which is appointed by the prime minister and has wide-ranging access to top secret intelligence reports, meets behind closed doors.
It reports to Mr Blair and the government can delete "sensitive intelligence material" from the committee's reports before they go public.
Because their inquiries deal with the general use of intelligence in the run-up to war with Iraq, they might not provide clear-cut evidence one way or the other over the BBC claims.
When will we get the first of these reports?
The Foreign Affairs Committee report is due to be published on 7 July.