LONDON, (Reuters) – Britain expects to be able to withdraw “thousands” of its troops from Iraq by the end of 2007, Britain’s Defence Minister Des Browne said on Monday.

Browne refused to give specific numbers, but said: “By the end of next year I expect numbers for British forces in Iraq to be significantly lower by a matter of thousands.”

Military planners have been working on a possible troop reduction for some months, Browne said a speech in London. He also called on neighbours Iran and Syria to give Iraq their “full and undivided support”.

Britain has around 7,200 troops in southern Iraq, mostly stationed in and around Basra, the country’s second largest city. Shi’ite factions are battling each other for control of the oil-rich area and British troops are sometimes attacked.

The government is coming under increased political pressure to bring soldiers home and Foreign Minister Margaret Beckett said last week Britain hoped to hand over control of Basra to Iraqi forces early next year. “I have been asking our planners to look at all the options to make sure we do not ask a single soldier to remain in Iraq longer than is necessary,” said Browne.

Britain has already handed over control of Muthanna and Dhi Qar, two of the four southern provinces it took responsibility for after the U.S.-led invasion in 2003. Maysan province is due to meet the conditions for handover in January.

Browne stressed any 2007 troop reduction would only be possible if efforts to boost Iraq’s own security capabilities went according to plan and that it was contingent on the Iraqi government’s wishes. “We need to be clear that handover does not mean withdrawal,” he said, adding that it was not worth speculating whether there might be any longer-term presence. “The situation in the long term in Iraq will of course depend on the Iraqi government’s expectation of us,” he said. There have been growing calls for Washington to engage with Iran and Syria to stop Iraq descending into civil war and Browne said Iran would face isolation unless it played a positive role. “Its behaviour remains a cause of deep concern,” he said. “Support from within Iran goes to groups who are attacking our forces, but also to groups who are simply fuelling the sectarian violence. This is unacceptable.” “So the message to Iran is simple. Be a constructive partner, help yourself as well as the wider region or face increasing isolation.”