Nato will continue to train Afghan special forces outside the country after it winds up 18 years of security work in the conflict-torn country, the military organisation’s top civilian official has said.

Speaking after talks with the French president Emmanuel Macron in Paris, Nato Secretary General Jens Stoltenberg said: “As we end our military presence, we are opening a new chapter.”

Stoltenberg said Nato’s revised role would involve giving “advice and capacity-building support to Afghan security institutions, as well as continued financial support.”

He said Nato also plans “to provide military education and training outside Afghanistan focusing on Special Operations Forces.”

It was not immediately clear where the training will take place.

US military leaders are still grappling with how best to carry out President Joe Biden’s order to withdraw all American troops from Afghanistan by September while helping Afghan forces and monitoring the threat that prompted the US invasion of the country after the September 11 attacks in 2001.

America’s allies in Europe, plus Canada, rely on US logistical and transport help to operate in Afghanistan, and their troops are obliged to leave the country as well. Many officials have expressed concern that once the US leaves, the Afghan government and its armed forces will be quickly overrun by the Taliban.

It remains unclear what level of security might be needed, and who would provide it, to protect international embassies spread around the capital, Kabul. The city’s airport, the main international gateway to Afghanistan, must also be protected.

Stoltenberg said Nato plans to “fund the provision of services, including support for the functioning of Kabul airport.”

Asked for clarification, a Nato official said: “We’re now looking into the details and consulting on next steps.”

Violence is surging in the country. Roadside bombings in southern and central Afghanistan killed 13 people, including nine members of one family, officials said on Thursday.

Meanwhile, militants stopped a bus in the west of the country, ordered three men to get out before shooting and killing them.

No one claimed responsibility for the attacks. The government blamed the Taliban, who denied responsibility.