Gordon Brown was "aware of what was happening" as Britain edged closer to war with Iraq but was kept in the dark about some key developments, the inquiry heard today.
The Prime Minister said his predecessor Tony Blair would often discuss the "options" surrounding the conflict with other Cabinet figures.
But Mr Brown, then Chancellor, was not present at every meeting, the panel was told.
During his evidence, it also emerged Mr Brown:
* Was not shown an "options paper" drawn up by the Cabinet Office in March 2002;
* Did not know attorney general Lord Goldsmith had wavered on a decision to give legal backing for the war;
* Had not seen private letters sent by Mr Blair to US president George Bush assuring British support for any military action;
* Was not present at all war cabinet meetings.
Mr Brown insisted that Cabinet had been "informed fully" about the process of negotiations ahead of the invasion.
But, in his evidence to the panel, he indicated that he was not at the heart of the decision-making process.
Former international development secretary Clare Short told the inquiry previously that Mr Brown was "marginalised" in the run-up to the invasion.
Mr Brown confirmed in his evidence that he was "not involved" in every meeting Mr Blair had with other members of the Cabinet.
"In the different committees, obviously the Prime Minister was talking to the Foreign Secretary and the Defence Secretary about the options," said Mr Brown.
"I was not involved in those discussions but I was aware of what was happening."
The inquiry heard that Mr Brown was not shown an "options paper" to outline various choices for dealing with Iraq, from continuing sanctions to launching regime change.
The Prime Minister said: "I don't recall seeing that paper. My main involvement in looking at the options started from June."
He added: "I don't think I needed to see every paper."
Although unaware of the attorney general's change of heart over the legality of the invasion, Mr Brown said this would not have affected his decision once "unequivocal" backing had been given.
"I don't think it would have changed my view," he said.
Mr Brown told the panel he attended as many war cabinet meetings as possible - but was not at each one.
And he acknowledged he had not seen the private correspondence between Mr Blair and Mr Bush.Reuse content