Two British soldiers were killed by a suicide bomber during a mission intended to reassure local Afghans.

The members of the 3rd Battalion, The Rifles, who were attacked while on a joint patrol with Afghan forces near Sangin, Helmand province, are expected to be formally named later today.

The Ministry of Defence (MoD) said the soldiers were on foot patrol at the time of the explosion, in which two Afghan National Army soldiers also died.

News of yesterday’s fatalities came after the first of 500 extra British troops arrived in Afghanistan and Defence Secretary Bob Ainsworth announced a package of cutbacks in core defence programmes to fund £900 million of new equipment for troops in the country.

The deaths brought the total number of British service personnel to have died since the start of operations in Afghanistan in 2001 to 239. There have been 102 deaths this year alone.

Lieutenant Colonel David Wakefield, spokesman for Task Force Helmand, said: “It is with deep sadness I must inform you that two British soldiers were killed this afternoon near Sangin in northern Helmand province.

“They were both from 3rd Battalion, The Rifles. They will be sorely missed by us, their comrades, but their sacrifice will not be forgotten.”

The MoD was unable to confirm local reports that the soldiers died after two suicide bombers on a motorcycle attacked a military convoy.

An MoD statement added: “During the course of a joint Afghan National Army and International Security Assistance Force security patrol, designed to reassure local Afghans, two British soldiers from the 3rd Battalion, The Rifles were killed as a result of a suspected suicide improvised explosive device explosion.”