Shell’s claims to clean up the oil spills in Niger Delta are “blatantly false”, according to a new report.

Amnesty International has also accused the Nigerian Government for failing to regulate the oil industry.

It claims the country’s watchdog, the National Oil Spill Detection and Response Agency (NOSDRA), is “under-resourced and continues to certify areas as clean that are visibly polluted with crude oil”.

In 2011 pollution caused by oil spills from Shell pipelines in the region were exposed. In response, Shell said it would clean up the sites but four which were identified as “highly polluted” were still “visibly contaminated in 2015”.

Niger Delta is said to be the biggest oil-producing region in Africa. Shell operates around 50 oil fields and 5,000 km of pipelines, “much of them ageing and poorly-maintained”, Amnesty International claims.

Citing Shell’s figures it adds there has been 1,693 oil spills since 2007, “although the real number is probably higher”.

Mark Dummett, Business and Human Rights researcher at Amnesty International, said: “Anyone who visits these spill sites can see and smell for themselves how the pollution has spread across the land.”

Amnesty International claims contractor who was hired by Shell said: “This is just a cover up. If you just dig down a few metres you find oil. We just excavated, then shifted the soil away, then covered it all up again.”

A Shell spokesperson added: “The report has only just been released this morning, therefore it is difficult to verify and respond to the detailed claims made by this organisation.

“Implementation of the UNEP [United Nations Environment Programme] report is part of a wider programme of remediation, pipeline protection, community engagement and social investment activities being undertaken by the SPDC JV [Shell Nigeria] with its government, community and civil society partners in Ogoniland.

“SPDC JV is committed to cleaning up all spills from its facilities, irrespective of cause.”