A Nigerian oil technocrat has emerged as frontrunner to take the top job at Opec, with members seeing Mohammed Barkindo as what would be a rare compromise candidate to lead the group amid rising tensions between Saudi Arabia and Iran.

Barkindo has been a key face of the Nigerian oil industry for the past decade, during which various governments tried and effectively failed to reform national oil company NNPC.

Today, Nigeria has alongside Venezuela become one of the main victims of oil's price collapse, with the country's output declining sharply due to militant attacks on pipelines and infrastructure.

Opec is likely to choose Barkindo, a former head of NNPC, as the next secretary-general of the producer group, three sources with knowledge of the matter said.

The Organization of the Petroleum Exporting Countries has since 2012 been looking for a replacement for Libya's Abdullah Al-Badri, who was elected acting secretary-general in December until the end of July after serving full terms.

However, Barkindo's appointment was by no means certain and Badri's tenure could yet be extended by another six months, some sources said.

Rivalries between Opec heavyweights Saudi Arabia, Iran and Iraq have so far prevented the group from choosing candidates proposed by those countries.

Opec oil ministers meet on Thursday in Vienna. The consensus of all members - which in the past has sometimes been elusive - is required for the appointment of a new secretary-general.

Barkindo led the Nigerian National Petroleum Corporation from 2009 to 2010 and served as acting secretary-general of Opec in 2006 after the original Nigerian nominee, junior oil minister Edmund Daukouro, took over the rotating Opec presidency.

Barkindo also served on Opec's economic commission and held various high-ranking positions during a career at NNPC that spanned over two decades.

He was deputy managing director of the Nigerian Liquefied Natural Gas Company, a joint venture between NNPC, Shell Gas BV, Total and Eni.

He was also head of NNPC's London office, managing director of NNPC's oil and gas trading division, and an NNPC group executive director.

"He's a reasonably safe pair of hands and good for a more administrative role like secretary-general. He also knows the ropes at Opec from when he was Lukman's (right-hand man)," a senior industry source with close ties to Nigeria said.

Rilwanu Lukman was influential in Nigeria's oil industry for many years. He served as oil minister during military rule and later as secretary-general to Opec and special adviser on oil to former president Olusegun Obasanjo.

"Don't expect any fireworks, either positive or negative," the industry source said. - Reuters