Libya's new army chief Khalifa Haftar on Monday promised his forces would seize Benghazi from Islamist militias within a month and called for wider support from the international community.

In an interview with AFP at his military compound about 100 kilometres (60 miles) northeast of second city Benghazi, he said his forces would press to take the city by the middle of April and urged the international community to "stand with the Libyan army".

"We will end in very little time the presence of the enemy and terrorists in the region. Operations in the city of Benghazi will end before the middle of next month," Haftar said.

"No doubt the international community knows the depth of the crisis Libya is experiencing since the overthrow of Moamer Kadhafi, with the absence of law, public order and the rise of militant groups" linked to the Islamic State organisation, he said.

Haftar, 72, was sworn in on March 9 as the new army chief in conflict-ridden Libya and promoted to general, a week after his nomination by the elected parliament.

He said that Islamist militias have flourished in the absence of public institutions, "pushing the country further towards extremism and terrorism" and "stripping Libyans of life, security and development".

He said the offensive in Benghazi, which he has dubbed Operation Dignity, was to "answer the repeated calls of the Libyan people for the return of the army to combat terrorism in the region".

Last May, Haftar launched an offensive against Islamists in the country's east focused on Benghazi but has so far failed to take the city.

- 'Modern' Libyan military -

He said "the Libyan army does not and would not interfere in the political process because it is the guardian and protector against anyone trying to disrupt the democratic process by force."

Haftar added he plans to rebuild his military's infrastructure to match "modern" standards, while fighting Islamist militias at the same time.

Since the 2011 overthrow of Kadhafi in a NATO-backed uprising, Libya has been wracked by conflict, with rival governments and powerful militias battling for control of key cities and the country's oil riches.

The North African country has two parliaments and two governments.

The internationally recognised legislature was elected in June and is based in the eastern city of Tobruk, while the rival Islamist-backed General National Congress (GNC) is in the capital, Tripoli.

The Tobruk government has repeatedly asked the UN Security Council sanctions committee to lift an arms embargo imposed following the 2011 uprising.

Britain, France and the United States oppose scrapping the embargo, arguing that it would fuel violence, but diplomats have stressed that arms contracts can be approved by the sanctions committee on a case-by-case basis.

Earlier this month the United Nations put on hold its approval to allow the internationally backed government in Libya to buy fighter jets.

Last week EU foreign ministers gave the green light for the bloc to prepare a possible security mission in Libya once the country's warring factions agree a national unity government, as talks between them continue.

Talks between the rival parliaments on forming a unity government are due to resume on Thursday in Morocco, the United Nations has said.