LONDON: Tony Blair's controversial former chief spin doctor Alastair Campbell gave evidence to a public inquiry into the Iraq war on Tuesday, days before his one-time boss takes the stand.

Campbell, one of the ex prime minister's closest allies, is the first big name witness to appear before the Chilcot inquiry to face questions about the intelligence the government used to make the case for war.

After arriving amid a scrum of press photographers, Campbell's three-hour evidence session started with him launching a typically feisty defence of his "very" close relationship with Blair.

"If he asked me to jump off a building, I wouldn't have done it, if he asked me to do anything silly or stupid, I wouldn't have done it, but he never did," Campbell said.

He also said current Prime Minister Gordon Brown, who was then finance minister, would "absolutely" have been one of the "key ministers" Blair discussed decisions on Iraq with.

Blair is due to appear in late January or early February, while Brown will not be called until after this year's general election, which is expected to be held in May.

Campbell, Downing Street's former director of communications and strategy, resigned in August 2003, the month after Ministry of Defence weapons expert Dr. David Kelly was found dead near his home with slashed wrists.

Earlier that year, he fiercely denied a BBC report that he "sexed up" a dossier claiming Iraq could launch a chemical or biological attack within 45 minutes to help justify the war.

Kelly believed he may have been the source of the BBC's story and officials confirmed his name as such to some reporters.

Campbell insisted he had decided to resign to spend more time with his family well before Kelly's death.

An official inquiry -- one of several probes to which he has already given evidence over the Iraq war -- subsequently exonerated him over the affair.

Campbell has kept a relatively low profile since leaving Downing Street, publishing his memoirs and a novel about a psychiatrist.

He is also advising Brown's ruling Labour party informally ahead of this year's general election and co-founded an Internet campaign to drum up grassroots Labour support.

Some Labour figures are reportedly worried that his evidence could revive memories of the unpopular Iraq war and cause Labour problems on the campaign trail for the election, which must be held by June.

The former premier faced a major backlash over the decision to stand shoulder-to-shoulder with then US president George W. Bush over the war. He resigned in 2007 despite having led his Labour party to three election wins.

Blair insisted last month he would have supported the war, which did not gain explicit United Nations approval, even if he had known Iraq did not have weapons of mass destruction.

The Iraq inquiry, led by retired top civil servant John Chilcot, has faced claims from some critics that it is not questioning witnesses rigorously enough.

But Chilcot hit back last month, insisting it was "not here to provide public sport or entertainment" but "to get to the facts."

The Daily Mail newspaper said in an editorial Tuesday that Campbell, who worked for Blair for nine years, "must face the toughest possible grilling" over how Britain became involved in the Iraq war.

"Only when we have all the facts can we begin to ensure it never happens again," it added.