The 110th US Congress was formally convened today, ending 12 years of Republican dominance on Capitol Hill and offering the first glimpse of the political landscape in which President George Bush will see out his presidency.

Members of the Democratic Party, led by America's first female Speaker of the House, Nancy Pelosi, preached the need for co-operation with the White House but wasted no time in assuring their supporters that the Republican grip on all three branches of the US Government was over.

"Today we make history. Today we change the direction of our country," said Ms Pelosi, a congresswoman from San Francisco, as she prepared to launch a volley of six pieces of legislation on issues including the minimum wage, stem cell research and new ethics rules for politicians.

In the Senate where the Democrats hold a majority of just one Senator Harry Reid, the majority leader, began on a more restrained note by calling a rare, closed-door meeting with the aim of instilling a new spirit of bipartisanship in the chamber.

"Our efforts are going to be to work in a bipartisan basis in an open fashion to solve the problems of the American people," he said.

Vice President Dick Cheney, acting in his capacity as president of the Senate, swore in the 33 senators who won seats in November, while on the other side of the Capitol all 435 members of the House of Representatives, including Keith Ellison, America's first Muslim congressman, began a new two-year-term.

"In this House, we may belong to different parties, but we serve one country. We stand united in our pride and prayers for our men and women in the armed forces. They are working together to protect America, and we, in this House, must also work together to build a future worthy of their sacrifice," said Ms Pelosi at her formal swearing in.

Democrats were also keen to suggest that they will bring a new style of business to Washington.

Democrat-led congressional hearings are expected on the conduct of the war in Iraq as well as further calls for the Bush Administration to follow the recommendations of the Iraq Study Group and reduce the number of US troops in the country.

But in their first 100 hours of control on Capitol Hill, the chief Democratic goal appeared to be to make good on Ms Pelosi's pledge that this will be "the most honest, ethical, and open Congress in history".

A new raft of ethics proposals - a conscious attempt to do away with the climate of corruption that surrounded their Republican rivals during November's elections - stood out among the six bills that will be tabled over the coming days.

The rules, which go beyond earlier Democratic proposals, forbid outright the use of corporate jets by politicians and impose further restrictions on gifts and travel paid for companies and other outside interests.

The proposal also suggests considering the establishment of an independent panel to monitor the behaviour of Congress, a move previously resisted by both parties.

Many of the proposals, particularly those aimed at gifts and travel expenses, appear aimed at correcting abuses performed by Jack Abramoff, the former Republican lobbyist sentenced to five years and ten months imprisonment for bribery and fraud last year, and Tom DeLay, the former Republican House Majority Leader.

Abramoff's case caused the party serious problems during last year's congressional election campaigns and yesterday, on the last official day of Republican control on Capitol Hill, his influence was still apparent as two Republican congressmen, Curt Weldon of Pennsylvania and Tom Feeney of Florida, agreed to pay back nearly $30,000 of travel costs paid for by his firm.

Another practice targeted by the Democrats is the so-called "K Street Project", a tactic used by Mr DeLay, who resigned last year to fight charges of money laundering, to influence the hiring of Washington's top lobbying firms. Under the new rules politicians will be banned from leaning on the firms to appoint friends and party supporters.

On Friday, the newly convened House of Representatives will also be asked to consider new rules governing so-called "earmarks", pet projects inserted into big spending bills, often to the benefit of a single politician. Under the proposals all "earmarks" would have to be listed separately with the identity of their sponsors made known.

On a day of pomp and celebration for the Democrats some Republicans presented a contrite face. John McCain, the Republican Senator from Arizona who is expected to run for the presidency in 2008, told NBC this morning that he was "very sad" that the Republicans had lost their majority but blamed his own party.

"We forgot why we came to Washington," he said. "We lost our way.... we valued power over principle and we paid a heavy price for it."

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