Oil cartel Opec is considering enlarging its membership for the first time in more than 30 years.
Nigeria, the current president of the Organisation of the Petroleum Exporting Countries, is considering granting membership to Sudan and Angola, already observer members.
Oil ministers of the 11-nation oil producer group are meeting in Caracas, Venezuela today to discuss the current energy situation. They are not expected to boost supplies.
Opec is expected to leave oil production quotas unchanged at 28 million barrels per day (bpd).
Venezuela has argued for a cut in the daily quota because of the strong supplies at present.
Angola and Sudan are two of the world's fastest-growing oil producers. Angola produces 1.25 million bpd; Sudan produces about 360,000 bpd.
Should Nigeria give the go ahead, Opec's grip on world oil supply would grow from 41 to 43 per cent.
But analysts said accepting Sudan and Angola may step on the footprint of China, which counts Sudan as one of its most important sources of foreign oil assets and Angola's reserves are much coveted by BP, Total and Eni, ExxonMobil and US firm Chevron.
Unconfirmed reports claim that Nigerian president Olusegun Obasanjo has sent a letter to his Sudanese counterpart Omar Al-Bashir inviting his country to join the group.
Oil slipped yesterday nearly $2 on the news that the US wished to join in talks with Opec producer Iran if Tehran suspended its nuclear enrichment programme.