Nato representative in Kabul says 2014 deadline for ending combat role might not be met

Afghanistan could experience "eye-watering" levels of violence after foreign combat troops withdraw from Afghanistan in four years' time, the Nato representative in Kabul warned today.

Mark Sedwill, the civilian counterpart to US commander General David Petraeus, also said that the target of handing over security responsibilities to the Afghan army and police by the end of 2014 might not be met.

The alliance's plan for the "transition" of responsibilities from Nato's International Security Assistance Force (ISAF) to the still embryonic Afghan army and police will be high on the agenda at this week's Nato summit in Lisbon.

Many European countries that contribute troops see the plan as their ticket out of an unpopular war, but Sedwill warned that success was not guaranteed and the 2014 date was merely an "inflection point" in a campaign that would continue for a long time. In some areas of the country transition could run "to 2015 and beyond" he said.

Although the alliance hopes that foreign-led counterinsurgency operations will come to an end, troops would still be required to train and support the Afghan security forces and maintain "a strategic over watch" position, he said.

He conceded that a "residual insurgency" was likely to continue in many parts of the country.

"There would still be a certain level of violence and probably levels of violence that by western standards will be pretty eye-watering," he said.

In such a scenario special forces units would be required to remain and fight, he said, in addition to the logistical support, training and equipment provided for Afghan units.

Sedwill said that with so many uncertainties, Nato's 2014 deadline was "realistic but not guaranteed".

He also warned that transition was "not a cheap option" that would allow troops to leave quickly. "We are not looking at forces flooding out of this country as transition starts. One of the key principles of this is you reinvest the transition dividend."

Nato is refusing to announce where the transition process will start for fear of turning those districts into targets for insurgents to increase their operations and mount intimidation campaigns against government officials.

Sedwill said that he expected Nato to hand over several provinces in the first half of next year. However, he said the transfer of responsibility for both security and development activities would vary across the country.

In some areas, entire provinces would be transferred, while in others it would be districts, or even individual towns. Transition would take between 18 and 24 months in some areas, depending on the resilience of the insurgency and the capability of the Afghan army, police and the village militia-style "local police" that are being established.

The Afghan police and army are being built up at breakneck speed. Both institutions remain beset with problems, including widespread illiteracy and drug abuse. The army has also struggled to recruit among southern Pashtuns, the group that predominates in areas of the country most affected by insurgency.

The head of the Nato training mission, General William Caldwell, has complained that he does not have enough trainers to meet the transition deadline.

The attempt to create an army and police up to the job of taking over requires vast sums of money.

Even after they have been built up to strength, officials say they will cost around $6bn (£3.7bn) a year to run – about half of Afghanistan's current GDP and more than the US gives to both Israel and Egypt.

Sedwill said the IMF had calculated that Afghanistan woukd not be able to pay for its own security forces until 2023.