Libya's government and armed forces on Friday moved to quash rumours of an impending coup after a retired general called for parliament and the government to be suspended.

In a video posted on the Internet, Khalifa Haftar announced an "initiative" under which the interim authorities would be suspended.

Both the prime minister and the head of the armed forces responded by pouring scorn on the idea of a coup d'etat.

Haftar commanded ground forces during the 2011 uprising that overthrew the 42-year dictatorship of Moamer Kadhafi.

"The command of the Libyan national army announces its initiative for a roadmap, that will be made public in the coming days" in consultation with different parties, Haftar said in the video.

The initiative foresees the suspension of the General National Congress (GNC), Libya's highest political authority, and the transitional government.

It also looks to the formation of a presidential commission headed by the president of the Higher Judicial Council.

"The Libyan national army has decided to act... not in order to govern but to prepare the proper conditions" for elections, Haftar said.

After Haftar's video was released, rumours quickly spread on social networks that a coup may be in the offing.

"It's a lie. The situation is under control and there is no suspect movement," the army chief of staff's spokesman Colonel Ali al-Shikhi told AFP.

Prime Minister Ali Zeidan called the rumours "ridiculous", saying that Haftar "is not a member of the military".

"He was retired," Zeidan said, adding that state institutions were functioning normally.

It is not known if the former general has any support among the ranks of the army or from powerful groups of former rebels.

Analysts also said that Haftar's initiative did not amount to an attempted coup by the military.

"The army is trying to break Libya's current political deadlock but is too small and weak to be able to take over government in Tripoli and enforce its writ," said Anna Boyd, senior Middle East analyst with IHS Country Risk.

"There is no indication that the army has made any move to seize power, for instance by surrounding government buildings," she said.

"Haftar does have support from officers in eastern Libya concerned about Islamist influence inside Libya's GNC, but it is very unlikely that he speaks for the whole army."

Haftar, originally from eastern Libya where the revolt against Kadhafi erupted in February 2011, served under the strongman before defecting in the late 1980s.

He returned to join the rebels after spending more than two decades in the United States.

Haftar's video comes after the GNC on February 3 took the controversial decision to extend its mandate until December, despite opposition by much of the population critical of its inability to halt Libya's slide into chaos.

The authorities have struggled to restore law and order in the troubled aftermath of the Kadhafi era.