Britain has officially handed over its Iraq headquarters to the US as troops prepare to leave the country.

The flag of 20 Armoured Brigade was lowered at the British base in Basra and was replaced with a US flag in a formal ceremony marking the transfer of authority to the Americans a month earlier than planned.

The pullout of the bulk of the 3,700 UK troops remaining in Iraq will now speed up in the coming days.

Defence Secretary John Hutton flew into Basra for a service to honour the 179 British personnel who lost their lives in the conflict.

UK troops carried out their final patrols outside the main coalition military base in Basra before handing over to the Americans.

Speaking at a news conference with Iraqi Prime Minister Nouri Al-Maliki, Gordon Brown said the pullout would mark a "long-term partnership of equals" between the UK and Iraq.

Despite the formal end of offensive operations by British troops today, they retain the right to defend themselves and their convoys if they come under attack.

The UK handed military control of coalition troops in Basra to the US army at the end of March. All but about 400 of the remaining British troops in Iraq will be withdrawn by July 31.

Mr Hutton stood with his head bowed as the names of the 179 British personnel who died during Operation Telic - the UK military mission in Iraq - were called out.

This was followed by the reading of the names of the American, Danish, Italian, Dutch and Romanian troops and the civilian contractors killed in southern Iraq since 2003.

Brigadier Tom Beckett, commander of 20th Armoured Brigade, read the traditional verse: "At the going down of the sun, and in the morning, we will remember them."

Then bugler Gareth Roberts, 25, from Shrewsbury, of 5 Rifles, played the Last Post and the troops saluted their fallen comrades during a minute's silence.

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