Nato troops should be sent to volatile south Afghanistan to boost security and counter the drugs trade, Defence Minister John Reid has said.
John Reid (R) meets Afghan President Hamid Karzai in Kabul
Mr Reid, who is visiting Afghanistan, said differences within Nato on whether its troops should take an offensive role would have to be "worked through".
France, Germany and Spain believe Nato troops should keep to peacekeeping.
Nato has 12,000 peacekeepers mainly in the more stable north and west. The UK takes command of them next May.
Mr Reid was speaking after meeting Afghan Defence Minister Rahim Wardak in Kabul.
"We want to contribute to the south, not only in counter-narcotics... but also in creating a framework for economic alternatives to flourish," Mr Reid said.
The US has been pushing for Nato to take a more offensive role to ease the pressure on its Operation Enduring Freedom against militants who operate mainly in the south and east.
The US has about 18,000 troops in Afghanistan.
The UK will lead the Nato force from May and run the headquarters of its rapid reaction force.
Britain is expected to deploy Nato troops to Helmand in the south, one of the provinces that has seen an upsurge of Taleban-linked violence this year.
France, Germany and Spain oppose an offensive role for Nato peacekeepers, but Mr Reid said he believed they had no "particular problems" with a move south.
On Friday, the British defence ministry said a big increase in the UK contingent in Afghanistan was being considered.
Defence sources said as many as 4,000 soldiers could be added to the 900 British troops.
Mr Reid admitted a move to Helmand could bring British fatalities, but added: "It is not a matter of casualties, but a matter of trying to avoid innocent casualties of terrorism."
The US has lost more than 50 troops this year, making it the worst year for its military fatalities since the fall of the Taleban in December 2001.