The US ambassador to Iraq assured Congress yesterday that despite a recent rash of insurgent attacks, Iraq is standing firm against a return to widespread sectarian violence.

Christopher Hill, in his first congressional testimony since taking up his diplomatic post in Baghdad in April, said Iraqis have not "risen to the bait" posed by al-Qaida and others seeking to rekindle warfare between Sunnis and Shi'ite.

"The reality is that the Iraqis have stood firm and have rejected retribution and a new cycle of violence," Hill told the House Foreign Affairs Committee.

One reason for the brake on a return to sectarian warfare, Hill added, is that Iraqi security forces have progressed so far in professional development that they are seen by ordinary Iraqis as being committed to "play it fair and they do their jobs".

Too early to tell

Meanwhile, the number two American commander in Iraq told reporters at the Defence Department that it is too early to tell whether officials will be able to go forward with a possible acceleration of the drawdown of US troops.

Defence Secretary Robert Gates in July cited the possibility that an extra combat brigade of 5,000 American troops might be brought home early from Iraq if the trend of reduced violence held. It was the first suggestion that the Obama administration might rethink its decision to keep as many forces in Iraq as possible this year ahead of Iraq's upcoming national election.

Asked if an accelerated withdrawal still seems a possibility, Lieutenant General Charles Jacoby said: "We'll see how the environment improves as we head toward the election.

"I will tell you that it's a volatile time period" now, Jacoby told Pentagon reporters in a video conference from Iraq, where he said he believes home-grown al-Qaida fighters are responsible for most of the recent spectacular deadly bombings.

In his congressional testimony, Hill said the US is on track to removing all its combat forces from Iraq by next August. And he says the US is moving towards a civilian-led effort to develop a long-term relationship with Iraq.