Treasury chief Gordon Brown, expected to succeed Tony Blair as prime minister by September, suggested Sunday that he will pursue an Iraq policy that is more independent of Washington than the current government.

Brown acknowledged that mistakes were made in the aftermath of the invasion and promised to be "very frank" with President Bush. He also said that Britain is likely to scale down its commitment of troops to Iraq over the next year — even as the White House is considering dispatching thousands more, at least temporarily.

Brown's comments, aired on the British Broadcasting Corp.'s Sunday AM program, seemed intended to distinguish himself from Blair, who has been criticized in Britain for his strong support for Bush and the war, both unpopular here.

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"I look forward, if I am in a new position, to working with the president of the United States, George Bush," Brown said. "Obviously, people who know me know that I will speak my mind. I will be very frank. The British national interest is what I and my colleagues are about."

A spokesman for the U.S. State Department declined to comment on Brown's interview.

Blair has said he will step down as prime minister and leader of the governing Labour party before September. Brown, who is credited with helping Blair reinvigorate the Labour party, is unlikely to face any credible challenge when the party elects a new leader, who will automatically become Britain's new prime minister.

Brown, in the BBC interview, also said that Saddam Hussein's execution — in which Saddam, a Sunni Arab, was taunted with the name of a radical Shiite cleric — had done nothing to help stem Iraq's sectarian violence.

"Now that we know the full picture of what happened, we can sum this up as a deplorable set of events," Brown told the BBC. "It is something, of course, which the Iraqi government has now expressed its anxiety and shame at."

Blair, who previously declined to comment on the hanging, said through his press office Sunday that the manner of Saddam's execution was "completely wrong."

Brown also told the BBC that he believed the ideological battle for the hearts and minds of young Muslims was as crucial as the battle against communism was for previous generations.

Brown, in charge of Britain's Treasury since 1997, said he had worked with officials across the American political divide and remained close to ex-Federal Reserve chairman Alan Greenspan and former Treasury Secretary Robert Rubin.

In the interview, recorded on Saturday, Brown also said he believed there should be some form of inquiry into the aftermath of the 2003 U.S.-led invasion.

"There are lessons to be learnt, particularly from what happened immediately after Saddam Hussein fell," he told the BBC.

"One is that in Iraq itself there is absolutely no doubt — and I think people will agree on this in time — that the passage of authority to the local population should have begun a lot earlier, so they had to take more responsibility for what was happening in their own country."

He said the experience of insurgency in Iraq and Islamic extremist terrorism had proven that "we will not win against extreme terrorist activities and propaganda activities unless we have this battle for hearts and minds as well."

The Treasury chief said he believed Britain was unlikely to join any future U.S. plan to temporarily increase troop numbers in Iraq, aimed at stemming the current bloodshed.

Britain would "continue to move troops from combat to training, to complete the redevelopment work" and was likely to scale down their presence over the next few months.

Britain has around 7,000 soldiers stationed in southern Iraq, mainly based around the city of Basra.

"I believe it is true to say that by the end of the year, there may be thousands less in Iraq than there are now," Brown said.

Parliament would also have a stronger role under his leadership, Brown said, and be more able to hold the government to account.

Complete coverage is available in FOXNews.com's Iraq Center.