The formal handover of sovereignty in Iraq took place at a low key ceremony in Baghdad yesterday.

The handover had been scheduled for Wednesday - but was secretly brought forward.

Paul Bremer, the US special administrator, left the country shortly after handing over to interim prime minister Iyad Allawi.

The move is being seen as an attempt to stop insurgents conducting a terror spectacular to overshadow the handover.

Meanwhile, in Istanbul NATO leaders gathered amid tight security for a summit dominated by the future of Iraq.

Tony Blair joined world leaders including President Bush for the Istanbul talks.

Bush was passed a note saying "Mr President: Iraq is sovereign".

The two coalition leaders welcomed the handover of sovereignty.

Blair said that the move was "an important staging post on the journey of the people of Iraq towards a new future".