KABUL : Afghan security officers shot dead two would-be suicide bombers in a Kabul restaurant before they were able to launch an attack, a senior government official said on Thursday.

Deputy Interior Minister General Ayoub Salangi said two gunmen, wearing explosive vests, entered the restaurant but were immediately shot by two agents from the National Directorate of Security, the Afghan intelligence agency, who were on the premises. NATO Secretary-General Jens Stoltenberg told reporters flatly: "I sense that many allies are willing to stay longer if needed." Although Afghan forces have recaptured the strategic northern city of Kunduz, its brief fall to the Taliban last month underscored concerns about the capabilities of Afghanistan's security forces.

U.S. President Barack Obama had aimed to withdraw all but a small U.S. force before leaving office, pinning his hopes on training and equipping local forces to contain Taliban militants fighting to return to power.

Washington has spent around $65 billion on preparing the fledgling Afghan security forces of about 350,000 personnel. But that is still very far from complete. Carter said he was preparing a U.S. funding request to sustain Afghan troops at their target peak levels of around 350,000 in 2017 "and beyond".