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

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

"A guideline of our partnership with the Libyan people will be always be respect for Libya's independence and sovereignty," the assistant secretary of state for Near Eastern affairs told a news conference.

"This is a victory by the Libyan people and Libya's destiny must be decided by Libyans alone," he said after meeting the head of Libya's National Transitional Council, Mustafa Abdel Jalil.

His visit came as a top-level team from the African Union, which has refused to recognise the NTC, began to discuss ways to press for an inclusive Libyan government at a gathering in Pretoria, South Africa.

Feltman paid tribute to the work of NTC in overseeing the transition from Kadhafi's 42 years of iron-fisted rule.

US Secretary of State Hillary Clinton, he said, had been reassured after the NTC renewed its commitment to respecting rights and promised to investigate allegations of abuses following a damning report by Amnesty International.

"I told chairman Jalil that Secretary Clinton particularly welcomed his recent restatements of the (NTC's) commitments to human rights, reconciliation and to inclusive transition progress, recognising the important roles of women and youth."

Another group, the Mali-based Defence of Foreigners in Libya, on Wednesday accused Libya's new authorities of jailing and torturing some 300 foreigners, mostly Tuaregs from Mali and Niger, suspected of being Kadhafi backers.

"Tuaregs are being tortured, hunted in the streets," said the NGO, citing the case of six reported missing and rumoured to have been killed and buried in a mass grave, according to testimony gathered in Libya.

EU foreign affairs chief Catherine Ashton expressed concern over the reported rights violations, notably towards sub-Saharan Africans.

"I remain very concerned at recent reports of human rights violations in Libya, including cases of arbitrary detention and extra-judicial killings," Ashton said in a statement.

Ahead of the AU meeting, South Africa's Foreign Minister Maite Nkoana-Mashabane had said it was not enough for Libya's new government to be headed by Abdel Jalil, who was justice minister under Kadhafi.

"I don't think if you have one or two people we would then say this is all-inclusive, because you have picked one person from that part of the world," she said.

Nkoana-Mashabane insisted the NTC knew "exactly what the AU meant by an all-inclusive interim government" but she stopped short of saying Kadhafi loyalists should be included.

But the difficulty of bringing together Libya's various factions was brought to bear by criticism of Abdel Jalil's number two in the NTC, Mahmud Jibril.

Islamist leader Sheikh Ali Sallabi accused Jibril of "stealing the revolution" and laying the foundations for a totalitarian state by appointing Ali Tarhuni to head the oil portfolio at the expense of more experienced managers.

"The premise of a totalitarian state is palpable by the action of Mahmud Jibril, who seeks to give his relatives the means to control the state," said Sallabi, who is supported by Qatar, and has played a key role in funding and arming the fighters of the new Libyan leadership.

In neighbouring Niger, Kadhafi's son Saadi was under guard in the capital Niamey after fleeing Libya at the weekend, but NATO acknowledged it has no idea where the toppled despot himself is holed up.

The alliance stressed Kadhafi was not a target in the daily bombing campaign it has kept up against his remaining forces, which still control a swathe of the coast around his hometown of Sirte as well as a string of Saharan oases.

Saadi, 38, the third of Kadhafi's seven sons, is among 32 officials of the ousted regime, three of them top generals, who have fled through the desert to neighbouring Niger this month.

He was flown into Niamey late on Tuesday after being put on an air force Hercules C-130 transport plane from the northwestern town of Agadez, Nigerien officials said.

Washington accepted Niamey's assurances that Saadi, who commanded an elite army unit after a brief career as a professional footballer in Italy, was in the custody of Nigerian security forces.

"Our understanding is, like the others, he's being detained in a state guest house," State Department spokeswoman Victoria Nuland said.

"It's essentially a house arrest in this government facility, is our understanding," she added.

NATO -- whose latest strikes hit targets around Sirte, Waddan and Zillah -- said it had no idea whether Kadhafi himself had also fled his country.

Colonel Roland Lavoie, spokesman for NATO's Libya mission, said the alliance had received, at "various points" in the conflict, intelligence confirming Kadhafi was still in Libya, but that his whereabouts were now a mystery.

The commander of US forces in Africa, General Carter Ham, said Kadhafi still has small pockets of loyal fighters in Sirte and Bani Walid, but that his ability to influence events "has largely been eliminated."

Meanwhile, diplomats in New York said Wednesday that Britain hopes that a vote will be held within three days on a United Nations Security Council resolution it has drafted setting up a UN mission in Libya.