Fears of Shia backlash against hardline tactics

Britain's ministers and military commanders are seriously concerned that attempts to rein in Shia militia, notably Moqtada al-Sadr's Mahdi army, in Baghdad could provoke his supporters in the Shia-dominated south, where British troops are based.

"If the situation gets worse in Basra the UK will be under pressure to do something similar [to the US]", a former senior British military officer said.

It was partly to pre-empt such an outcome that Gen Sir Richard Dannatt, the new head of the army, publicly expressed the hope in interviews last autumn that British troops should leave Iraq "sometime soon", making it clear that he meant within two years.

Despite the talk of symmetry in public, with Tony Blair's spokesman saying Britain was working "hand in glove" with its coalition partners and the Iraqi government, it seemed clear yesterday that the British and American paths in Iraq are diverging.

"The south is very different" was the refrain across Whitehall - in Downing Street, the Foreign Office, and at the Ministry of Defence.

Officials said Operation Sinbad - involving about 1,000 British troops and aimed at insurgents and criminals, particularly elements inside the city's police force - had proved a success. The MoD drove home the point yesterday by revealing that the operation is starting a new phase - or "pulse", as the military call it - with Iraqi forces engaged for the first time without any British troops.

The operation has been conducted by Maj Gen Richard Shirreff, the British commander in Basra who admitted last month that British ambitions in Iraq had been scaled back. He said: "When I set up, came up here and initiated the operations we have been conducting, I was looking for a 100% solution. But this is Iraq, this is Arabia and this is reality, so a 60% solution is good enough for me."

Despite fears of a Shia backlash against the new tactics Mr Bush says US troops will deploy around Baghdad, the British government hopes it will not be deviated from its long-held ambition to cut the number of British troops in southern Iraq - there are currently about 7,200 - by half in May.

The Iraqi police force in Basra, British officials admit, will still be riddled with corruption and the influence of Shia militia, but they insist that the Iraqi army in the south is developing into an effective force.

But Britain's timetable for troop withdrawal is dictated as much by the pressures on Britain's armed forces, the army in particular, and the belief now shared by ministers and chiefs of staff that in stark contrast to their role in Iraq, their mission in Afghanistan is a "noble cause".

Lt Gen Graeme Lamb, deputy commander of foreign troops in Iraq and Britain's most senior officer in the country, said in a dispatch just published on the MoD's website: "Military efforts can only set the conditions for a political solution for the reconciliation needed to reduce violence."

British officials were hoping yesterday that over the next few months Mr Bush's new strategy will have been seen to help, rather than hinder, such a process.

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