British troops have already had a peacekeeping role in Kabul
Britain is to send more troops to Afghanistan to help the newly-formed government maintain control over local warlords.
For the first time British troops will be used as peacekeepers outside the capital Kabul.
A total of 60 troops are due to arrive early next month in the city of Mazar-e-Sharif, working as a "provincial reconstruction team".
A further eight teams which will not all be British-led will be created for other cities later.
Afghanistan's transitional government has struggled
to impose its authority outside Kabul since the US-led war ended 18
Crime and disorder are described as rife throughout Afghanistan, and the country is the
world's leading exporter of opium.
Insecurity in the country may mean the postponement of next year's elections, according to the United Nations.
Eighty aid agencies have also warned their ability to work in many parts of the country may be at risk after a sharp rise in attacks over the last two months.
Announcing the deployment of the extra troops in May, Defence Secretary Geoff Hoon said the
team would focus on improving dialogue between local warlords and politicians.
The new national army is still in its infancy
The team would remain in Afghanistan for up to two years, he said.
"The role of these teams is to aid the extension of the Afghan transitional
authority's capacity, the development of a stable and secure environment in the
Afghan regions and to stimulate security sector reform and reconstruction.
"By encouraging and facilitating dialogue between all the political groups
and militias around Mazar-e-Sharif, the team will contribute towards the Afghans
themselves creating a safer and more stable environment," Mr Hoon said.
Britain led the peacekeeping force, the International Security Assistance Force (Isaf), for six months in Afghanistan last year to help the interim government maintain security in Kabul.
It also sent Royal Marines to southern Afghanistan.
But defence correspondent Andrew Gilligan said
Britain largely withdrew from both these roles last year because of overstretch in the build-up for Iraq.
The US has been leading a number of military operations in recent months against the Taleban, amid fears it is regrouping.
Earlier this week, the Taleban leader, Mullah Mohammed Omar was reported to have organised a new war council to fight the US-led forces.