LISBON - NATO will continue its mission in Libya as long as there is any threat to the country's population from forces loyal to Muammar Gadhafi, the head of the western alliance said on Thursday.

NATO's Secretary-General Anders Fogh Rasmussen told reporters in Lisbon that after the threat had gone, the alliance's role would be a supporting one.

"NATO and our partners will continue the mission as long as the threat remains, but not a minute longer," he said after meeting Portuguese Foreign Minister Paulo Portas.

"Gadhafi and the remains of his machine must realise that there is nothing to be gained from more fighting."

Earlier on Thursday, the former Libyan leader vowed to defeat the National Transitional Council (NTC) that controls most of the country in a phone call aired by a Syrian television station.

Rasmussen also said NATO's mission in Libya had prevented a massacre.

"We have prevented a massacre of the Libyan people, we saved numerous lives and it is now for the NTC and the Libyan people to shape a future for the country and ensure a peaceful transition to democracy," he said.

"Our operation in Libya has been a great success, we have operated on a UN mandate with the aim to protect civilians."