The first full-scale inquiry into Britain's role in the Iraq war opened with testimony suggesting Washington was gearing up for possible conflict two years before Tony Blair led London to war.
More than six years after the US-led invasion, inquiry chairman John Chilcot said no one was "on trial" in the
year-long probe but promised not to shy away from criticism as he seeks to learn lessons from the conflict.
The highlight of the public inquiry will be an appearance by then prime minister Blair, who is due to give evidence in
The first day of hearings was dominated by testimony from top civil servants who told how some in the US administration were already considering toppling Saddam Hussein's Iraqi regime two years before the 2003 invasion.
However, they said Britain distanced itself from these "voices" and said they remained sidelined even within the
United States until after the September 11, 2001, attacks in New York and Washington.
"No one is on trial here. We cannot determine guilt or innocence. Only a court can do that," Chilcot said in his
"But I make a commitment here that once we get to our final report, we will not shy away from making criticisms,
either of institutions or processes or individuals, where they are truly warranted."
The US said it was willing to cooperate with the inquiry.