Kabul is Nato's first major assignment outside Europe

The move is an attempt to improve security ahead of elections next year.

Soldiers and development workers have been sent to the southern region of Kandahar - the former Taleban stronghold - to extend the authority of President Hamid Karzai.

It is the eighth such peacekeeping group - or Provincial Reconstruction Team (PRT) - to be deployed.

Other PRTs have been already sent to the south-eastern city of Gardez, Baminan in central Afghanistan, and Mazar-e-Sharif and Kunduz in the north.

Four more PRTs are expected to be sent to the south and east Afghanistan next year to counter suspected Taleban forces attacking the US-led troops.

'Unstable'

The advantage of PRTs is that they are area-specific, and can bring some security to a district, says a BBC correspondent.

They also allow development agencies to respond to the particular needs of a region

However, in practice, PRTs are small and have to operate within very limited guidelines.

Their restricted mandate means PRT soldiers cannot get involved in green-on-green fighting (factional clashes), they cannot intervene if they see human rights abuses, and they cannot stop drugs production.

Afghanistan remains unstable with factions in the north launching almost daily attacks on the south.

There is also rising drug-related violence in much of the country.