Baghdad - The British military on Tuesday formally transferred control of its base in the southern Iraqi city of Basra to US forces in a military ceremony attended by Iraqi leaders.

The transfer follows Britain's agreement last year to withdraw all but 500 of the 4,100 troops it had stationed in Iraq ahead of its complete military withdrawal from the country in July.

The 500 remaining British soldiers will train Iraqi forces, the Iraqi navy in particular.

After the United States, Britain sent the largest contingent of soldiers to support the 2003 invasion of Iraq.

British troops transferred the responsibility of operating Basra's civilian airport to Iraqi authorities on January 1, but the British military retained control of the military base next to the airport. Control of that base will now pass to the US military.

Though calm has largely returned to Basra, the base has frequently been the target of rocket attacks.