British forces in Iraq could hand over responsibility for security in Basra to Iraq within nine months, defence sources said yesterday.

A senior military commander said a full handover was "feasible" in nine to 12 months.

British forces could be cut from 7,000 troops to between 3,000 and 4,000 by mid 2007, he added.

Sources stressed any handover would be dependent on the security situationand the agreement of the Iraqi government.

Even once security is handed over, the British would expect a significant presence - probably in one or two bases around Basra.

"We anticipate there is not going to be a political appetite to say 'job done' while there is still unfinished business," one commander said. "We started this as a coalition and we need to protect our investment."

The British have already handed over responsibility in al Muthanna - one of four provinces in their sector.

An announcement on Dhi Kar province could come this week, while they are in the process of pulling out of the main base in Maysan province where forces will now concentrate on patrolling the Iranian border.

Of the provinces, Basra has always been the most difficult, with violence linked to the militias such as the radical cleric Moqtada al Sadr's Mahdi Army.

Sources said while the Iraqi army was making progress, there were still "problems" with the police which suffered from infiltration by militias.

"There are rogue elements, some of them alarmingly close to the government," one commander said.

Officials said Iran was continuing to stir trouble across the border, although they did not believe the regime in Tehran wanted to see Iraq descend into complete chaos.

"The continuing worry we have is the appearance of technology - improvised explosive devices and others - which appears to be pretty well identical to what we have seen Hezbollah use in the past," one senior official said. "We all know that Hezbollah has a very close relationship with some parts of the Iranian government.

"The jury is still out on whether this is directed at the highest level by the Iranian government or whether it is elements within it."