Britain will withdraw around 1,600 troops from Iraq over the "coming months" and aims to cut its 7,100-strong force to below 5,000 by late summer if local forces can secure the southern part of the country, Prime Minister Tony Blair said Wednesday. British troops will remain in Iraq until at least 2008 and work to secure the Iran-Iraq border and maintain supply routes to US and coalition troops in central Iraq, Blair told the House of Commons. "The actual reduction in forces will be from the present 7,100 - itself down from over 9,000 two years ago and 40,000 at the time of the conflict - to roughly 5,500," Blair said. He told lawmakers that "increasingly our role will be support and training, and our numbers will be able to reduce accordingly." Blair said Iraqi Prime Minister Nouri al-Maliki had agreed to the plan. Dependent on Iraqi capability Britain would draw down further, "possibly to below 5,000" once a base at Basra Palace is transferred to Iraqi control in late summer, Blair said. "What all of this means is not that Basra is how we want it to be. But it does mean that the next chapter in Basra's history can be written by Iraqis," Blair said. Blair will make a statement to Britain's parliament on Iraq and the Middle East after the weekly House of Commons questions session, his spokesman said earlier.