Some of Libya's clans said on Wednesday they would not recognise the government, a day after the unveiling of a new cabinet revived regional and tribal rivalries which threaten the country's stability.
Prime minister designate Abdurrahim El-Keib named a cabinet line-up which aimed to placate Libya's patchwork of tribes, regional interests and ideological camps which are competing to fill the vacuum left by Muammar Gaddafi's fall from power.
The International Criminal Court (ICC) chief prosecutor, Luis Moreno-Ocampo, said during a visit to Tripoli that the trial of Gaddafi's captured son, Saif al-Islam, could take place inside Libya as long as certain conditions were met.
He also told Reuters that he believed Gaddafi's former intelligence chief Abdullah al-Senussi, like Saif al-Islam wanted for prosecution by the ICC, had not been captured. Libyan officials had earlier said he had been arrested.
The protests over the government were on a small scale and by groups which do not have huge influence.
There was no immediate sign of dissent over the cabinet from the most powerful interests, in particular the Islamists who were given none of the biggest government posts, but smaller groups complained they had been neglected.
Announcing the government was the latest step in Libya's halting progress towards building new institutions, three months after the bloodiest of the Arab Spring uprisings ended Gaddafi's 42-year rule.
The head of the National Transitional Council (NTC), the authority which oversees the government until elections are held, urged the protesters to put narrow interests to one side.
We didn't intentionally exclude or marginalise any entity or any place or any region or any ethnicity. Libya, on the contrary, is for everybody, Mustafa Abdel Jalil told a news conference.
We have to rally in one line behind this revolution which has been protected and safeguarded by Allah. And therefore we only ask them to have patience and to renounce envy and grudges, he said.
About 150 people protested on Wednesday morning outside a hotel in the eastern city of Benghazi where the interim leadership, the National Transitional Council, has offices, a witness told Reuters.
The protesters held up banners saying: No to a government of outsiders! the witness said. The demonstration was led by members of the Benghazi-based Awagi and Maghariba tribes, who were angry their representatives were not in key posts.
Elsewhere, a group calling itself the Libyan Amazigh Congress said in a statement it was suspending all relations with the NTC in protest at the choice of cabinet ministers.
The Amazigh, or Berber, are an ethnic minority which suffered persecution under Gaddafi and which is pressing for greater recognition for its language and culture in the new Libya.
In the predominantly Amazigh town of Jadu, in the Nafusa mountains south-west of Tripoli, about 30 young men gathered in a central square recruiting people to travel to the capital to demand better representation.
We are going to Tripoli to stage a peaceful sit-in to protest the ministerial appointments, one of the men, Tarek Yussef Labah, told Reuters. The Nafusa mountains were one of the first places to turn against Gaddafi.
The ICC earlier this year issued a warrant for Saif al-Islam's arrest on charges of crimes against humanity. After talks with Libyan officials, Moreno-Ocampo said the ICC would not insist on his transfer to The Hague for trial.
My standard, the standard of the ICC, is that it has to be a judicial process that is not organised to shield the suspect. That's it, Moreno-Ocampo told reporters.
The point is that for Libya, and I respect that, it is very important to do the cases in Libya. This is a right and I have nothing to say. I'm not competing for the case.
Saif al-Islam, dressed in traditional nomad attire, was captured on Saturday in an ambush in the Sahara desert. An NTC official said his arrest was the last chapter in the Libyan drama.
Western countries, which backed the revolt against Gaddafi and have a big stake in seeing his replacements succeed, welcomed the new government, saying it would guide the oil exporting country towards democracy.
The cabinet line-up appeared to be a setback for the Islamists who in the past few months have emerged as a powerful force and had been eying the post of defence minister. Islamist leaders have so far not reacted to the appointments.
By his choice of ministers, the Libyan prime minister is risking sparking a confrontation with Islamist leaders that could threaten the already delicate security environment in the country, the Eurasia Group consultancy wrote.
The NTC's choices to fill ministerial posts appeared to have put regional affiliation ahead of experience or a track record. Several seasoned officials were overlooked in favour of relative unknowns.
The leader of one of Tripoli's two most powerful anti-Gaddafi militias, which are trying to parlay their military muscle into political influence, said his men would respect the new government.
Abdullah Naker, head of the Tripoli Revolutionary Council, said the formation of the cabinet was the cue for ex-rebel militias to switch from war to politics.
He changed out of his usual military fatigues and arrived for a news conference in a suit and tie. We are going to start a civilian state, he said.
Naker told reporters the men under his command, who he said numbered nearly 100,000, would transfer their allegiance to the defence and interior ministries, though he did not say when that would happen.
He also said he was going to set up a political party to work for the rights of those men who took up arms to bring down Gaddafi. Libya has now become a democratic state, said Naker.
(Additional Reporting by Ali Shuaib and Marie-Louise Gumuchian and Oliver Holmes; Writing by Christian Lowe; Editing by Jon Hemming)