Kabul - British Prime Minister Gordon Brown arrived on a surprise visit in Afghanistan on Saturday, a day after four British soldiers were killed in suicide and roadside attacks in the southern region of the country, officials said.

A presidential palace source said Brown was scheduled to meet with Afghan President Hamid Karzai, and the two would hold a joint press conference later Saturday.

The official website for the prime minister said Brown would also pay a visit to his country troops. He last visited Afghanistan in August, when he pledged to continue British support for the country.

Brown's visit came a day after four British soldiers were killed in two separate blasts in Sangin district of southern Helmand province on Friday.

A Royal Marine was killed when his vehicle was struck by a roadside bomb. An hour later, three soldiers on foot patrol were killed after a 13-year-old boy approached them with a wheelbarrow in which a bomb was hidden, officials said.

Taliban militants took responsibility for the attacks.

About 8,000 British soldiers are stationed in Helmand province, as part of a 50,000-strong NATO force deployed to Afghanistan from 40 nations.

Helmand is the main hub for Taliban militants and foreign fighters associated with the movement. Helmand is also the largest opium producing province in the country.

Friday's deaths brought the total number of British troops killed in Afghanistan to 132. (dpa)