An Indian-flagged tanker has been forced to return a shipment of oil smuggled out of Libya thanks to international intervention, according to the country's National Oil Corporation (NOC).

‘The Indian vessel Distya Ameya, which was illegally attempting to export Libyan oil, has this morning... returned its unlawful cargo to Libya,’ it said in a statement posted on Saturday on its website.

The NOC instructed the tanker to discharge at the Zawiya refinery west of Tripoli, where it will be used ‘for the benefit of all Libyans’ in the cash-strapped country, it said.

‘I would like to thank all the people involved for helping to bring about a swift and safe resolution of this matter,’ said NOC chairman Mustafa Sanallah, praising the ‘action of the international community’.

The United Nations on Wednesday added the Distya Ameya to a UN sanctions blacklist after it left Libyan shores bound for Malta.

A UN Security Council diplomat said the tanker's final destination could be the United Arab Emirates and that the cargo violated a ban on oil revenues to entities other than Libya's unity government.

The UN-backed government has been striving to assert its authority in a country which has been in turmoil since the 2011 revolt that killed dictator Moamer Kadhafi.

Despite the existence of a rival administration, the Government of National Accord has won support from politicians, civil society leaders and state institutions, including the NOC and the central bank which are the depositors of Libya's oil wealth.

The GNA has established its headquarters in a Tripoli naval base, but still needs the formal endorsement of the country's elected parliament.

Oil is Libya's main natural resource, with reserves estimated at 48 billion barrels, the largest in Africa.

Libya had an output capacity of about 1.6 million barrels per day before the revolt, accounting for more than 95 percent of exports and 75 percent of the budget.

But production has slumped amid violence as rival forces battled for control of oil terminals.

‘In the last three years, we have lost close to $75 billion up to April 2016 due to blockades at our oil ports and oil pipelines by militias,’ the NOC said in its statement.

‘That is $20,000 for every adult in this country.

‘This is the money that could be rebuilding the country, providing for basic needs, medicines and healthcare, electricity, education and so on,’ it said.