A decade after the US-led invasion of Iraq, Americans remain divided over the war, with a majority believing it was a mistake, according to a poll released Monday.

The Gallup survey, the first since US forces withdrew from Iraq in December 2011, showed Americans are still split over the war, with 53 percent saying they regret the decision to invade and 42 percent saying it was not a mistake.

The poll indicated little change in public opinion since a survey in 2009, and strong support for the decision to invade among those who support the Republican party of former president George W. Bush, who launched the war.

Opposition to the war among Americans peaked in April 2008, when 63 percent called the invasion a mistake.

Among those who identify with or lean towards the Republican party, 66 percent said it was not a mistake to go to war.

But among Democrats, a large majority of 73 percent said the invasion was a mistake.

The Gallup poll was based on telephone interviews with 1,022 adults conducted March 7-10. The margin of error is plus or minus four percentage points.

The Bush administration launched the invasion of Iraq on the grounds that dictator Saddam Hussein had weapons of mass destruction and needed to be disarmed. No such weapons of mass destruction were ever found.