A Libyan unity government pulled together with UN backing moved to take power on Saturday night as the Tripoli-based Presidential Council called on the country’s institutions and the international community to stop dealing with any rival powers. 

The council said in a statement on Saturday that it had a majority of signatures approving the new government from the House of Representatives (HOR) – one of Libya’s two rival post-Gaddafi assemblies – as well as endorsement by other political figures. This amounted to a “green light to start work”, the council said.

The declaration suggests the Government of National Accord – nominated by the UN-backed Presidential Council – will seek to take power despite continuing opposition from hardliners in both of divided Libya’s competing parliaments: the eastern HOR and the rival General National Congress (GNC) in Tripoli.

Libya has had two rival administrations since mid-2014 when the recognised government was forced from Tripoli after a militia alliance including Islamists overran the capital.

On Saturday the council called on “all Libyan sovereign and public institutions and the heads of financial bodies to start communicating immediately with the Government of National Accord so as to hand over power in a peaceful and orderly manner”.

“The Presidential Council also calls on the international community and international and regional organisations ... to stop dealing with any executive power that does not follow the Government of National Accord.”

The declaration of a unity government raises the possibility of foreign troops being sent in to help it cement power. A plan has previously been outlined for an  Italian-led “advisory and training” contingent comprising 5,000 troops to enter Libya once invited by a recognised government.

The Presidential Council is tasked with overseeing a transition to end the political chaos and armed conflict that has plagued Libya since the fall of leader Muammar Gaddafi in 2011.

Western nations hope a unity government can help tackle a growing threat from Isis, which has used a security vacuum and political divisions in Libya to establish a foothold.

The Presidential Council nominated a unity government in February but recognition was held up by the failure of the HOR to vote to approve it. 

It is unclear when a unity government could move to Tripoli, where the security situation is still volatile and some armed factions may try to prevent it operating.

The deal to create the unity government was signed with limited Libyan support in Morocco in December.

Efforts to move the transition forward have been hampered by arguments over the structure of the new government, the balance of power between Libya’s different regions, and the future leadership of the armed forces.

The Presidential Council has itself been divided, with two of its nine members suspending their participation and twice refusing to put their names to proposed lists of ministers.

Under the plan, the Presidential Council would form the highest state body. The HOR would be the main legislature, with a second chamber formed from the GNC.

After the latest failure of the HOR to vote on the unity government last week, UN Libya envoy Martin Kobler reconvened the group that signed the December deal.

On Thursday the group urged the Presidential Council “to take all necessary measures to rapidly start working from the capital, Tripoli”, though they also appeared to call on the HOR to take further steps to endorse the unity government.