Afghanistan is likely to be "messy" after western troops pull out in 2014, Defence Secretary Philip Hammond admitted today.
Mr Hammond said there was little prospect of the Kabul-based government defeating the Taliban "outright", and the most it could hope for was securing key cities and infrastructure.
But he insisted there were grounds for "cautious optimism" that political compromises could be reached with some insurgents, and the situation could be stabilised in the longer term.
The frank assessment came as Mr Hammond gave evidence to the Commons Defence Committee.
"The ability to see a long-term sustainable peace in Afghanistan fundamentally rests upon a political compromise and political accommodation being made within that country between the different ethnic groups, the government and the Taliban," he told the MPs.
"Such an accommodation will require the active support of the neighbours, particularly Pakistan."
He said there appeared to be a growing recognition in Islamabad that it was "very much" in the country's interests for Afghanistan to be stable.
President Hamid Karzai's administration was also coming round to the idea of reaching out to Taliban elements, Mr Hammond said.
"In terms of the government I am not as close as my honourable friend the Foreign Secretary, but I sense there is a dawning realism, a commitment to actually trying to reach an accommodation with those elements of the Taliban that are prepared to renounce violence and distance themselves from al Qaida and international terrorism," he went on.
"It is going to be a slow and careful process. I do not expect dramatic progress but I think we are heading gently in the right direction rather than the wrong direction."
He predicted that when international troops end their combat role next year, Afghan forces would be able to "effectively hold the important parts of the country", such as cities, towns and key infrastructure.
"I would expect the situation to be messier than it is today with Isaf (the International Security Assistance Force) at present on the ground, but I sense that there is a growing recognition on both sides of this fight that neither side can win outright.
"The government cannot defeat the Taliban and secure every inch of Afghan space.
"The Taliban sense, and we have some evidence of acknowledgement of this, that they cannot defeat the government in military terms.
"So I think both sides will want to make progress ultimately to some kind of political accommodation."
Mr Hammond added: "Our own experience suggests that might not be a smooth process.
"It might go in fits and starts.
"There might be periods when it looks as though the political process is making way, there may be other periods when it looks as though the political process is stalled and the focus is on the ability of the security forces to maintain the ground. But I would expect slow and messy progress."
The Cabinet minister told the committee he believed a patchwork of "more or less formal" local ceasefires would develop.
Mr Hammond told the cross-party committee that the Ministry of Defence would only bring back equipment from Afghanistan that it needed. Unwanted kit would be sold, gifted or destroyed.
Of around 11,000 container units of equipment in the country, he predicted that around 6,500 would return to the UK.