Libyan Prime Minister Ali Zeidan's new cabinet was sworn in on Wednesday at the national assembly and officially took up their posts, in the absence of eight contested nominees.

Outgoing premier Abdel Rahim al-Kib transferred power to Zeidan in front of General National Congress members and diplomats in Tripoli and saw the appointment of the new premier and 23 of his 31 nominated ministers, who were approved by the GNC in October.

Four of the proposed ministers were rejected by Libya's anti-corruption body, including interior nominee Ashur Shwayel.

GNC representatives had reservations about another four, including the proposed foreign minister, and will decide in the coming days on whether or not to approve them.

GNC President Mohammed Megaryef praised what he said was a "milestone in the realization of the new Libya of democracy, pluralism and peaceful alternation of power."

Zeidan promised his government would be "strong and steadfast."

In an address to the nation shortly after the ceremony, he said the government's priorities would include restoring security and rebuilding the economy.

The chief task of the new government is to organize fresh elections within 12 months on the basis of a new constitution, which has yet to be drafted.

Kib's outgoing government, which was appointed in November 2011, was accused of "laxity" during its mandate, particularly in the face of powerful militias that have controlled parts of the country since last year's uprising ousted Moamer Kadhafi.

He said on Tuesday that many obstacles had hindered his government, notably the "collapse of all state structures," lack of security and the halting of oil production.

But he added that his government had nonetheless organised the country's first free elections in July, which were praised by the international community. (AFP)