OPEC's Secretary-General Mohammad Barkindo has died, Mele Kyari, the chief executive of Nigerian National Petroleum Corp said on Wednesday.
Barkindo, who was 63 years old, was due to step down at the end of this month after six years as OPEC's secretary-general, Reuters reported.
"We lost our esteemed Dr. Muhammad Sanusi Barkindo," Kyari said on Twitter, adding that he died late on Tuesday.
The death was a "great loss to his immediate family, the NNPC, our country Nigeria, the OPEC and the global energy community," he added.
Kyari said Barkindo died hours after meeting Nigerian President Muhammadu Buhari and giving the main speech at an energy summit in Abuja.
Barkindo said the oil and gas industry is "under siege" due to years of under-investment, adding that the resulting supply shortage could be eased if extra production from Iran and Venezuela was allowed to flow.
He began his career with the Nigerian Mining Corporation in 1982 before holding multiple roles over more than two decades at the Nigerian National Petroleum Corporation. Before leading OPEC, Barkindo served as the Deputy Managing Director of Nigerian Liquefied Natural Gas, a joint venture between NNPC and multinational oil giants Shell, Total and Eni.
Born in Yola, Nigeria, he attended undergraduate university in Nigeria before earning a post-graduate degree in petroleum economics from Oxford University in the UK and an MBA from Washington University in the US.
In March, Barkindo was named a distinguished fellow of the Atlantic Council, which holds an annual global energy forum that he frequently headlined and spoke at.