Angry oil workers have shut down all offices and facilities of the Nigerian National Petroleum Corporation, NNPC, in protest of Tuesday's splitting of the state oil company by the federal government.
There are fears of fresh fuel scarcity as a result of the protest.
The government had announced the unbundling of the NNPC into seven independent units.
Two major unions in the oil and gas sector had on Friday rejected the planned splitting.
The spokesperson for the Petroleum and Natural Gas Senior Staff Association of Nigeria, PENGASSAN, Emmanuel Ojugbana, had said that the union was not carried along in the decision to split the company.
Similarly, the president of the Nigeria Union of Petroleum and Natural Gas Workers (NUPENG), Igwe Achese, had said union would not accept the decision without knowing how the manpower that would operate in the 30 companies would be managed.
On Tuesday, the Minister of State for Petroleum Resources, Ibe Kachikwu, announced the unbundling of the oil company into seven independent units, namely Upstream, Downstream, Gas & Power Marketing, Refineries and Ventures, Corporate Planning & Services and Finance and Accounts.
Each of the units would be headed by chief executive officers, namely Bello Rabiu for Upstream; Henry Ikem-Onih (Downstream); Saudu Mohammed (Gas & Power Marketing); Anibor Kragha (Refineries), while Babatunde Adeniran would be in charge of Ventures.
The chief executive officer in charge of Finance & Services would be Isiaka Abdulrazaq, while the Executive Head, Corporate Services will be Isa Inuwa.
On the workers' fears, the minister said the exercise has a "zero sum in terms of job loss".
"The principle of restructuring approved by the President is that nobody losses work," he said. "I do not have the mandate of the president to create a job loss situation, but to try to ensure that everyone gets busy, unless for reasons of bad staff performance and fraud. There is no mass attempt to let people go."
He said the decision to embark on the restructuring followed an analysis of the number of staff, which revealed that the corporation was over-staffed, and therefore the need for them to be meaningfully engaged.
The only way to realize that objective, the minister said, was to create jobs for everybody in the system to him enable have something doing.
"We don't want people coming to the office to read newspapers. We want everybody to get busy and earn money. If we do that we will realise that there would be adequate staff to man the different units, and that we don't really have the problem of over-staff after all," he said.