Loud blasts from apparent NATO airstrikes have rocked the Libyan capital, while fierce fighting has erupted between government forces and rebels near a western oil port.

Western news reports say several loud explosions shook Tripoli late Saturday after what had been a mostly quiet day in the capital.

Meanwhile, witnesses say clashes have erupted between forces loyal to Libyan leader Moammar Gadhafi and rebels in Zawiya, a oil port town about 50 kilometers west of Tripoli. A highway that serves as a major supply route between Tripoli and Tunisia is closed as a result of the unrest.

Rebels briefly took control of Zawiya in March but were beaten back by pro-Gadhafi forces.

Pro-government forces have also been pounding targets in the western town of Zlitan as well as in the rebel-held city of Misrata, where medical officials say at least 30 people were killed on Friday.

U.S. officials traveling with Secretary of State Hillary Clinton in Africa say Libya's situation will be featured prominently in her remarks on Tuesday at an African Union meeting in Ethiopia.

There was no indication Mr. Gadhafi was ready to end his reign, but Turkish Prime Minister Recep Tayyip Erdogan said Friday his government has offered him “guarantees” if he were to leave the country.

He did not specify the nature of the guarantees. But he said Turkey would help Mr. Gadhafi get to where he “would like.” Mr. Erdogan said he was still awaiting a reply from Tripoli.