NATO defence ministers were due Wednesday to discuss the final phase of security transition in Afghanistan with the country's Defence Minister Bismillah Mohammadi and their International Security Assistance Force (ISAF) partners, dpa reported.
"Afghan forces are now in the lead, showing courage, confidence and increasing capability," NATO Secretary General Anders Fogh Rasmussen said on Tuesday.
NATO is now preparing a mission to train and support Afghan forces after its combat operations end there in 2014.
Several steps are outstanding however, including a bilateral deal to be struck between Washington and Kabul, and a separate agreement spelling out NATO's role in the country. Without this legal basis, NATO has said there can be no new deployment to Afghanistan.
"I am confident that we will conclude security agreements with Afghanistan," Rasmussen said. "I'm confident ... because the Afghans know that such agreements are a prerequisite for our deployment of trainers after 2014."
"I do believe that the Afghans would like to see us continue training, advising, assisting the Afghan security forces," the NATO chief added.
The size of a post-2014 NATO mission to Afghanistan is also yet to be determined, with talk of a far smaller operation than the present one, encompassing around 8,000 to 12,000 personnel.
The second day of defence talks in Brussels was to begin with a meeting of the NATO-Russia council, giving ministers a chance to meet with their Russian counterpart, Sergei Shoigu, for the first time since 2011.
Issues are to include existing cooperation in areas such as counter-terrorism and support for Afghan forces, but also tensions between both sides over NATO's plans for a missile defence shield in Europe, which Russia says could be used to shoot down its missiles.
"NATO has invited Russia to cooperate in this field, and that offer stands," Rasmussen said.
The two sides would likely also discuss "current international security issues," said NATO spokeswoman Oana Lungescu. This was expected to include an exchange of views on developments in Syria, sources said.