Foreign Secretary Jack Straw urged the international community to support Iraq and its people as the results of its historic elections were announced.
Jack Straw urged the international community to support Iraq
He said Iraqis had taken an important step on the way to "a secure and democratic future", but still faced a "difficult task ahead".
A Shia-dominated coalition won nearly half of the 8.5 million votes cast in the election, poll officials said.
Kurdish parties came second, while Prime Minister Ilyad Allawi was third.
Welcoming the provisional results, Mr Straw said: "I wish the new members of the Transitional National Authority well in their important first task of electing a Presidency Council to oversee the new executive of Iraq.
"Subsequently, of course, we wish them well in overseeing the drafting of Iraq's permanent constitution."
Shia list: 48%
Kurdish list: 26%
Iyad Allawi list: 14%
He reiterated United Nations secretary general Kofi Annan's comments that "it is crucial for the future of Iraq that the full diversity of Iraqi society is represented in the political and constitutional process".
There is now a three-day period for complaints about the results to be lodged. If none are upheld they become official.
Iraqi officials said turnout in the 30 January poll was about 58%, but many of the Sunni minority did not take part.
Provisional results were announced on 13 February
Iraq's election commission said the coalition of religious Shia Muslim candidates, assembled by the Grand Ayatollah Ali Sistani, received about 48% of the vote.
The Kurdish parties took about 26%, while the list led by Mr Allawi was a distant third with nearly 14% of the vote.
The main Shia list of candidates - the United Iraqi Alliance - will be granted the most seats in the new 275-member assembly, and is expected to nominate the new prime minister.