There have been reports of surging demand for African energy supplies from the EU that is seeking to wean itself of dependence on Russian oil and gas.

"This gas pipeline is to take gas to 15 West African countries and to Morocco and through Morocco to Spain and Europe," said Timipre Sylva, the minister of state for petroleum resources.

"It is only after the engineering design of the pipeline that we will know exactly (what) the cost of the pipeline will be. When that time comes, we will be talking about funding," he added.

Nigeria is a member of the Opec group of major oil producers and has huge gas reserves - the largest proven reserves in Africa and the seventh largest globally.

On 30 May, Tanzania transported 60,000 tonnes of coal to the Netherlands.

Last month, Botswana President Mokgweetsi Masisi said European nations had "flooded" his country with requests to supply coal.