The alliance warned on Tuesday it would target facilities including factories, warehouses and agricultural sites being used by loyalist troops.

The warning came a day after foreign reporters were taken to Zliten, east of Tripoli, by government minders and shown what they were told was the remains of a clinic hit by a NATO bomb that killed seven people.

Alliance military spokesman Colonel Roland Lavoie said in Brussels that in recent days NATO had hit a concrete factory near Brega where regime forces were hiding and firing multi-barrel rocket launchers.

"Pro-Qadhafi forces are increasingly occupying facilities which once held a civilian purpose," Lavoie told reporters in a video conference from the operation's headquarters in Naples, Italy.

"By occupying and using these facilities the regime has transformed them into military installations from which it commands and conducts attacks, causing them to lose their formerly protected status and rendering them valid and necessary military objectives for NATO," Lavoie said.

Earlier, a NATO official said the alliance had "no evidence" that civilian facilities were hit in air raids near Zliten on Monday.

Baghdadi Mahmudi, the Libyan premier, reiterated on Tuesday that Kadhafi's departure is "not up for discussion," after meeting UN special envoy to Libya Abdul Ilah al-Khatib.

"The departure from power of Colonel Qadhafi is not up for discussion," he told a news conference after British Foreign Secretary William Hague demanded on Monday that Qadhafi step down but said he might be allowed to stay in the country.

"With all due respect to the British foreign minister, it is not up to him to take decisions on behalf of the Libyan people."

UN Humanitarian Coordinator for Libya Laurence Hart said in a statement a week-long fact-finding UN mission to Libya had identified several problems besetting Qadhafi's regime, which has been battling rebel forces for the past five months.

"Although the mission observed aspects of normalcy in Tripoli, members identified pockets of vulnerability where people need urgent humanitarian assistance," Hart's statement said.

The health sector is under strain, having lost thousands of foreign workers at the beginning of the conflict, it said.

Copyright APP (Associated Press of Pakistan), 2011

Copyright AFP (Agence France-Presse), 2011