The death takes the number of British troops killed in Afghanistan to 153
A British soldier has been killed in an explosion in southern Afghanistan, the Ministry of Defence said.
The soldier, from 1st Battalion Welsh Guards, died in the blast which occurred during a foot patrol north east of Gereshk in Helmand Province.
The soldier was taking part in the patrol along with soldiers from the Afghan National Army.
The number of UK troops killed on operations in Afghanistan since 2001 now stands at 153.
The MoD said the cause of the explosion was being investigated and that the soldier's next of kin had been informed.
Squadron Leader Wayne Palmer, spokesman for Task Force Helmand, said: "The loss of a Guardsman, and a colleague, has come as a huge blow to us all.
"But it is the family, friends and loved ones, as well as the men and women who served alongside him, who feel the greatest pain and we offer them our deepest and heartfelt condolences, thoughts and prayers."
An MoD spokeswoman said: "The soldier was taking part in a reassurance foot patrol alongside the Afghan National Army in the vicinity of Forward Operating Base Keenan, north east of Gereshk in Helmand Province when the incident happened.
"Despite the very best efforts of his colleagues around him, he was killed instantly as a result of an explosion, the cause of which is being investigated."