The UK death toll in Afghanistan has topped that of the Falklands war following the death of the 256th British soldier.

The latest casualty, a soldier from 36 Engineer Regiment, part of the counter-IED Task Force, was killed on Monday by an explosion in Nad-e-Ali, Afghanistan, said the Ministry of Defence. Next of kin have been informed.

Lieutenant Colonel David Wakefield, spokesman for Task Force Helmand, said: "His indomitable courage and fortitude, the hallmark of his profession, will not be forgotten."

A total of 256 British servicemen and women have now died since operations in Afghanistan began in October 2001.

Operation Moshtarak, a major offensive against insurgents in central Helmand, is due to begin in the coming days.

Speaking before the latest death, Defence Secretary Bob Ainsworth warned that British casualties were a "very real risk" during the bid to clear militants from areas surrounding the town of Marjah in Helmand.

He said on Monday: "We have seen an intense, hard and bloody period in Afghanistan but, as we prepare to consolidate our progress with the launch of Operation Moshtarak, it is imperative that we hold our resolve. The national security of the UK and the safety of its citizens depends on that."

Taliban fighters have been given the choice of laying down their weapons or facing "overwhelming force" from thousands of UK, US and Afghan troops.

Chief of the Defence, Staff Air Chief Marshal Sir Jock Stirrup, said while the Falklands milestone would attract attention, British troops would continue their work regardless.

He said: "Sad milestones such as this naturally attract attention in the UK, but in theatre our people continue resolutely and courageously with the task of assisting Afghans to build their own future."