US:California Democrat Nancy Pelosi has been sworn in as the first female speaker of the House of Representatives as her party took control of both houses of Congress after 12 years of Republican dominance.
Raising the speaker's gavel to a sustained ovation from both sides of the House, Ms Pelosi said she would preside in a spirit of partnership rather than partisanship.
"This is a historic moment - for the Congress and for the women of this country. It is a moment for which we have waited more than 200 years. Never losing faith, we waited through the many years of struggle to achieve our rights. . . For our daughters and granddaughters, today we have broken the marble ceiling," she said.
The new speaker said that voters wanted a change of direction in America, particularly where the Iraq war is concerned.
"It is the responsibility of the president to articulate a new plan for Iraq that makes it clear to the Iraqis that they must defend their own streets and their own security, a plan that promotes stability in the region, and that allows us to responsibly redeploy American forces," she said.
Ms Pelosi promised to introduce without delay a number of measures Democrats campaigned on in last November's election, including an increase in the minimum wage and new ethics rules in response to Republican congressional scandals.
Democrats rose and cheered after Ms Pelosi was elected with 233 votes - the entire Democratic caucus in the House - compared to 202 for Republican John Boehner.
Democrats started work on ethics reform last night, proposing new rules that would ban congressmen from accepting gifts, travel or meals from lobbyists or from organisations that employ lobbying firms.
The House will discuss further reforms today, including changes to the way "earmarks" - last-minute additions that often benefit congressmen's districts or individual businesses - are added to spending Bills.
Ms Pelosi has promised to move six Bills through the House within the first 100 legislative hours of the new Congress, including more funding for embryonic stem cell research.
The Democratic leadership in the Senate is introducing similar measures and the Senate will also consider a new immigration reform Bill that would offer an estimated 11 million illegal immigrants the chance to remain in the US legally and eventually apply for citizenship. The new Bill is based on a measure approved by the Senate last year but removes controversial elements, such as the requirement that undocumented immigrants return to a border entry point before regularising their status.
Incoming Senate majority leader Harry Reid rejected President George Bush's warning that Democrats were in danger of passing "simply political" measures.
"There is nothing political about finding a policy to end the war in Iraq, raising the minimum wage, achieving energy independence or helping kids afford college," Mr Reid said. "In fact, politics has prevented progress on these issues for too many years."
The 41 new Democratic members of the House include nine Irish-Americans. Massachusetts congressman Richard Neal, the incoming chairman of the congressional Friends of Ireland, said at a reception for new Irish-American members that the new Congress was committed to playing an active role in encouraging the Northern peace process.
As Mr Bush prepares to announce a new strategy for Iraq next week, Democrats have warned against increasing US troop levels, a proposal the administration is considering.
Republican senator John McCain, who supports a troop surge, warned against sending too small a force for too short a time to achieve victory in Iraq.
"To make it of short duration and small size would be the worst of all options to exercise in my opinion," he said.
Mr Bush's national intelligence director, John Negroponte, is to leave his role as co-ordinator of all 16 US intelligence agencies to become Condoleezza Rice's deputy secretary of state, according to US news reports.
Mr Negroponte is expected to be succeeded by retired admiral Mike McConnell, the director of the National Security Agency from 1992 to 1996, who spent more than 25 years as an intelligence operations and security officer.
White House legal counsel Harriet Miers, once nominated by Mr Bush for the Supreme Court, has resigned after six years working for the president.
Mr Bush nominated Ms Miers for the Supreme Court in October 2005 but she withdrew from consideration three weeks later after Republican senators questioned her qualifications and her stance on issues such as abortion and gay rights.