Forces loyal to Muammar Gadhafi have recaptured a town in Libya's mostly rebel-held east, rebel military officers said on Wednesday, in an attempt to break the momentum of a popular rebellion against his 41-year-old rule.



Forces sent by the Libyan leader had seized back Marsa El Brega after violent clashes with rebels who had controlled the town 800 km east of the capital Tripoli, the rebel officers told Reuters.



"It's true. There was aerial bombardment of Brega and Gaddafi's forces have taken it," Mohamed Yousef, an officer in the town of Ajdabiyah which is about 75 km (47 miles) from Brega, told Reuters on Wednesday.



The assaults are the most significant military success for Gadhafi since the uprising began two weeks ago and set off a confrontation that Washington says could descend into a long civil war unless the veteran strongman ruler steps down.



There are also fears that the uprising, the bloodiest yet against long-serving rulers in the Middle East, is causing a major humanitarian crisis, especially on the Tunisian border where thousands of foreign workers are trying to flee to safety.



Gadhafi is defiant and his son, Saif al-Islam, has warned the West against launching military action. He said the veteran ruler would not relinquish power or be driven into exile.



Across Libya, tribal leaders, officials, military officers and army units have defected to the rebel cause and say they are becoming more organized. Tripoli is a stronghold for Gadhafi in this oil-producing north African state.



"We are going to keep the pressure on Gadhafi until he steps down and allows the people of Libya to express themselves freely and determine their own future," Susan Rice, the U.S. ambassador to the United Nations, told ABC's "Good Morning America".



Captain Faris Zwei, among officers in the east who joined the opposition to Gadhafi, said there were more than 10,000 volunteers in Ajdabiyah, a short distance from Marsa El Brega.



"We are reorganizing the army, which was almost completely destroyed by Gadhafi and his gang before they left," he said. "We are reforming, as much as we can, the army from the youth that took part in the revolution."



Two amphibious assault ships, USS Kearsarge, which can carry 2,000 Marines, and USS Ponce, entered the Suez Canal on Wednesday en route to the Mediterranean. The destroyer USS Barry moved through the canal on Monday as part of efforts to increase diplomatic and military pressure on Gadhafi to quit.



The two ships entered through the southern end of the canal, an official said, adding that they were expected to pass through by 3:30 p.m. or 4:00 p.m. local time.



Arab League foreign ministers meet on Wednesday at an extraordinary session in Cairo and are expected to reinforce their condemnation of Gadhafi. Some delegates want the meeting to underline the League's unwillingness to see foreign intervention in Libya.



The repositioning of U.S. ships and aircraft closer to Libya is widely seen as a symbolic show of force since neither the United States nor its NATO allies have shown any appetite for direct military intervention in the turmoil that has seen Gadhafi lose control of large swaths of his country.



"We are looking at a lot of options and contingencies. No decisions have been made on any other actions," Defense Secretary Robert Gates said, noting the United Nations had not authorized the use of force in Libya.



Italy said it was sending a humanitarian mission to Tunisia to provide food and medical aid to as many as 10,000 people who had fled violence in Libya on its eastern border.



Tunisian border guards fired into the air on Tuesday to try to control a desperate crowd clamoring to cross the frontier.



Secretary of State Hillary Clinton said: "Libya could become a peaceful democracy or it could face protracted civil war."



The U.S. Senate, in a unanimous vote, approved a resolution "strongly condemning the gross and systematic violation of human rights in Libya, including violent attacks on protesters demanding democratic reforms".



The White House said the ships were being redeployed in preparation for possible humanitarian efforts but stressed it "was not taking any options off the table". Gates said: "Our job is to give the president the broadest possible decision space."



Analysts said Western leaders were in no mood to rush into conflict after drawn-out involvements in Afghanistan and Iraq.



Gadhafi, a survivor of past coup attempts, has told television networks: "All my people love me," dismissing the significance of the rebellion that has ended his control over much of oil-rich eastern Libya.



The Libyan leader has, however, faced defections from soldiers, diplomats and ministers. Gadhafi replaced two of his ministers who had defected to support the uprising seeking to oust him, Libyan state television said on Wednesday.



Despite the widespread collapse of Gadhafi's rule, his forces were also fighting back in the west. A reporter on the Tunisian border saw Libyan troops reassert control at a crossing abandoned on Monday, and residents of Nalut, about 60 km (35 miles) from the border, said they feared pro-Gadhafi forces were planning to recapture the town.



The UN General Assembly on Tuesday unanimously suspended Libya's membership in the UN Human Rights Council. A UN Security Council resolution on Saturday called for a freeze on Gadhafi's assets and a travel ban and refers his crackdown to the International Criminal Court.

Open gallery view Libyan pro Gadhafi supporters wave his posters during a march supporting leader Moammar Gadhafi in Tripoli, Libya, February 17, 2011. Credit: AP