Libya's UN-backed government on Tuesday called on the UN Security Council to block any "illegal sale" of oil by its eastern-based rival administration.

The move came after the eastern-based army announced on Monday that it would hand over the oil crescent region to the eastern-based government.

The UN-backed government criticizes in a statement the announcement of "unauthorized parties about handing over oil ports to an illegitimate and unrecognized entity."

The statement said the move is a "clear violation of the powers and specialties of the National Oil Corporation," stressing the Tripoli based corporation is the "only body authorized to manage oil ports and facilities."

"Such act ... will increase division and undermine years of local and international efforts to achieve stability," the statement said.

The government called on the UN Security Council and Sanctions Committee to "track and stop any illegal sale of oil that could take place as a result of these acts, in accordance with relevant international resolutions."

The eastern-based army spokesman Ahmed Mismari said on Monday that the army commander, Khalifa Haftar, has issued a decision to hand over the oil crescent region to the National Oil Corporation of the eastern-based interim government.

The army's announcement came a few days after taking over the oil crescent region and defeating the terrorists occupying it.

The oil crescent region is located some 500 km east of the capital Tripoli and contains the country's largest oil ports.

Despite signing a UN-sponsored peace agreement by the Libyan political parties in 2015, Libya remains politically divided between eastern and western governments, both competing for legitimacy.