Washington respects the right of Libyans to decide their own future, a senior U.S. official said Wednesday in Tripoli, as the African Union pushed for an inclusive government after Moammar Gadhafi's ouster.

"The United States respects Libya's sovereignty," said Jeffrey Feltman, the highest ranking U.S. official to visit the Libyan capital since its capture from Gadhafi’s forces on August 23.

The chief of Libya's revolutionary movement told thousands of cheering Libyans in Tripoli Monday to strive for a civil, democratic state, while loyalists of the hunted dictator Moammar Gadhafi killed at least 15 opposition fighters in an attack on a key oil town in Libya's east.

From hiding, Gadhafi urged his remaining followers to keep up the fight, a sign that Libya's six-month civil is not over even though revolutionary forces now control most of the country and have begun setting up a new government in the capital.

Amnesty International Tuesday accused the forces that overthrew Moammar Gadhafi of war crimes, saying Libya's National Transitional Council must act to stop reprisal attacks and arbitrary arrests.

A report by the human rights watchdog consists mainly of damning examples of violations by Gadhafi's regime but also outlines serious abuses committed by the new regime forces in a brutal settling of scores.

Libya's elusive former leader Moammar Gadhafi said he has no choice but to fight "until victory," in a message broadcast on Monday by Syria-based Arrai Oruba television.

In a statement read out by former Iraqi Sunni MP Mishan al-Juburi, who runs the television network, Gadhafi said "it is not possible to give Libya to the colonists again."

Patriotic songs composed by Libyan rebels during their revolt against Moammar Gadhafi fill the air every evening in Benghazi's Tahrir Square. After years of censorship under his ousted regime, a new music scene is taking off.

In the seafront former parking lot which became a key symbol of the seven-month uprising, an eclectic bazaar has sprung up at which vendors sell CDs and tapes honoring the conflict's "martyrs" and extolling the "free Libya."

Moammar Gadhafi’s forces put up unexpectedly fierce resistance Monday, launching a deadly raid on an oil refinery far behind the front lines even as the ousted despot's son Saadi fled to Niger.

Southeast of Tripoli, civilians poured out of the desert town of Bani Walid after intense fighting on Sunday between Gadhafi loyalists holed up in the sprawling oasis and encircling new regime troops, an Agence France Presse correspondent reported.

Russian President Dmitry Medvedev on Monday defended the Syrian regime against sanctions for its crackdown on protesters and warned British Prime Minister David Cameron of the dangers of such a move.

Cameron met Medvedev for talks focusing on Syria and bilateral disputes as global frustration mounted with Russia's continued support of its ally despite President Bashar al-Assad's months-long repression of nationwide protests.

A new transitional government will be formed in Libya within 10 days, the deputy chief of the National Transitional Council told reporters on Sunday.

"A new government will be formed within one week to ten days," said Mahmoud Jibril, who serves as the "prime minister" of the NTC, the political wing of the rebellion that overthrew strongman Moammar Gadhafi.

One of deposed Libyan leader Moammar Gadhafi’s sons, Al-Saadi Gadhafi, arrived Sunday in Niger, a government spokesman said.

"Today, September 11, a patrol of the Nigerien armed forces intercepted a convoy in which was found one of Gadhafi’s sons," Marou Amadou said.

Former rebel fighters clashed on Sunday with pro-Moammar Gadhafi forces at the oasis town of Bani Walid and were closing in on Sirte, poised for all-out assaults on the fallen leader's remaining strongholds.

Medics said at least two fighters were killed and 12 wounded in the skirmishes on the outskirts of Bani Walid, near to where forces loyal to Libya's new rulers were massed, waiting for the final signal to storm the town.