Britain may increase its military commitment in Afghanistan to help fill gaps in Nato's deployment there, a spokesman said.
UK troops could be used to fill gaps in Nato's deployment
James Appathurai, speaking for Nato's secretary general Jaap de Hoop Scheffer, said the UK was considering "potentially increasing" its force.
The Ministry of Defence has not confirmed any plan to reinforce the 7,700 UK troops already in Afghanistan.
These are mostly in Helmand province, in the south of the country.
Mr de Hoop Scheffer will call on member states to increase their military presence in Afghanistan at a Nato summit in the Netherlands on 24 and 25 October.
He played down the prospect that Canada or the Netherlands might downscale their presence in the south of Afghanistan.
Mr Appathurai told BBC Radio 4's The World This Weekend: "In the south, we don't think the Dutch are going to leave. The Canadians are looking at exactly what they can do.
"The British are talking in the south not only about keeping what they have but potentially increasing it.
"We are not pessimistic at all. We hope the Dutch will stay, we hope the Canadians will stay and we are working to convince them to do that in one form or another."
Politicians of all parties have previously said the UK is bearing too much of the burden in Afghanistan.