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ABUJA, Jan 18 (Reuters) - Nigerian lawmakers ordered an investigation on Thursday into whether the government could recover $21 billion in revenues from international oil companies.
Oil minister Emmanuel Ibe Kachikwu said in December the government had failed to enforce a legal provision entitling it to a greater share of crude sales once the price exceeded $20 a barrel.
Members of Nigeria's lower house of parliament voted to set up a committee to look into "the reasons for the loss", which the minister had estimated at $21 billion.
The committee would look into "the possibility of recovering the revenue lost," according to a statement on parliament's Twitter account.
The committee will ask the minister to provide details of financial transactions between the state oil firm and international oil companies and report back to parliament in six weeks, it added.
International oil companies in Nigeria include Shell , ExxonMobil, Chevron, Total and Eni.
In December, the oil minister said Nigeria was seeking to amend a law on deep offshore oil exploration and drilling, aiming to enforce the provision that the government take a greater share of crude sales when prices passed the $20 mark.
The minister said at the time that it would be difficult to recoup the historic losses, incurred since 1993, as the oil companies were not breaking the law.
Nigeria's government relies on oil for around two-thirds of its revenue, and is still largely dependent on crude production despite the current administration's attempts to diversify away from the industry. Those efforts have yielded few results, economic data shows. (Reporting by Paul Carsten; Editing by Elaine Hardcastle and Andrew Heavens)