NATO has said it is sending advisers to Libya to help Tripoli strengthen its security set-up amid chaos and fears of civil war two years after the armed uprising against Muammar Gaddafi.

The alliance "agreed to respond positively to the request made by the Libyan prime minister for NATO to provide advice on defence institution building in Libya", Secretary General Anders Fogh Rasmussen said on Monday.

The request for help was given added urgency by Zeidan's brief kidnapping by armed rebels this month. 

Two years after the violent death of Gaddafi in an armed uprising, Libya's fragile government is crippled by infighting and unable to disarm former fighters in a country awash with weapons from his four-decade rule.

The 28-nation alliance said it would set up a "small advisory team" to help Libya.

NATO provided few details about the mission or how many advisers would be involved, however a NATO source indicated to the Reuters news agency that their role would be to advise on strengthening the security forces rather than hands-on training.

The team will be based in Brussels and will not have a permanent presence in Libya, the source said.

NATO said its advisers would work closely with other international organisations and individual NATO members.

The alliance played a critical role in toppling Gaddafi, imposing a no-fly zone and using air power to try to prevent his forces attacking civilian areas held by rebels.

Source: Agencies