Des Browne, the British Defence Secretary, flew into Basra today to meet commanders on the ground as uncertainty hung over a plan to withdraw up to 1,600 British troops from southern Iraq by the spring amid claims of an increase in militia violence.

No decision has yet been made on troop levels and time is running out to reduce Britain’s contingent in the country to 2,500.

Gordon Brown said in the autumn that a final decision on the hoped-for withdrawal would depend on conditions on the ground.

In a sign of the ongoing challenges ahead, a roadside bomb killed 14 mourners travelling in a bus to Basra from a funeral in Najaf yesterday. A total of 18 people were wounded in the blast, which was aimed at a US convoy going in the opposite direction.

Iraq timeline: five years of conflict

From accusations that the weapons of mass destruction dossier had been sexed-up to withdrawal of British troops from Basra

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Iraqi officials, who took control of security in Basra from the British in December, have asked Baghdad for up to 6,000 extra troops to help to quell the unrest on top of a new brigade sent to the province last month.

Mr Browne attended an event at Basra airport, where British troops are largely based, in an event organised by the Iraqi Government to demonstrate its new capabilities at Iraq’s port in Umm Qasr.

He also met Major-General Barney White-Spunner, the senior British commander in Basra, as well as some soldiers.

The trip, described by a military spokesman as “routine”, comes at a time when future troop levels are in focus.

Lieutenant-General Bill Rollo, the most senior British officer in Iraq, has emphasised that the withdrawal plan hinged on assessments on the ground.

“There was a direction of travel and that is the aim and then we will judge it on conditions at the time, and that process is ongoing,” General Rollo told The Times. “I am not going to try and anticipate what the final figure will be.”

Asked whether there was a potential for troops to stay longer, given that it was spring already, he said: “There is a process that we will go through and we will get to the figure and we will know what the aim is.”

As for when that would be, he said: “It will still be the spring in April.”

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