Advocacy groups are calling on the Dutch oil giant Shell to halt its plans to divest assets from Nigeria's Niger Delta region unless proper cleanup and decommissioning of its infrastructure is complete.

This week, a Netherlands-based nonprofit released a report accusing Shell of trying to avoid responsibility for oil spills. The Center for Research on Multinational Corporations' report, entitled "Selling Out Nigeria — Shell's Irresponsible Divestment," said the Dutch oil giant's divestment in Nigeria must be suspended until clean-up and decommissioning of assets are complete.

The group accused Shell of trying to avoid responsibility for decades of oil spills in Nigeria's Niger Delta region that have polluted bodies of water and farmlands. It said Shell's assertion that it cleaned up polluted oil spill sites is flawed and cannot be trusted.

Faith Nwadishi, founder of Center for Transparency Advocacy, agrees with the report.

"The contract that they have signed that talks about the issue of remediation, protection of the environment and all of those things have not been done," said Nwadishi. "We should be looking at the contract and interpreting it accordingly — this is international best practice. This is what happens everywhere."

Shell operations grew controversial

Shell pioneered Nigeria's oil and gas explorations in 1937, but its operations have been subject to controversy and lawsuits from local communities.

Shell often blamed sabotage and vandalism by locals for busted pipelines, oil spills and environmental pollution.

In January, the company announced plans to sell its onshore operations to a local consortium of five companies for $2.4 billion.

Shell said the move would allow it to focus on more lucrative offshore businesses and that it was also proof that local companies are able to take on a larger share of Nigeria's oil and gas industry.

But Nwadishi said if the pollution issue is not addressed, Shell's exit could set a bad example for other multinationals operating in Nigeria.

"Once one person sets a precedent — especially the bad precedences — once they're set, you see other people following up," said Nwadishi. "When they do that, what it will mean is that they set a wrong template for other multinationals to do the same thing. And unfortunately, we have this judicial system that takes forever to take care of issues like that."

Law mandates funding for cleanup

Under Nigerian law, Shell is expected to provide funding for cleanup and decommissioning of its infrastructure before exiting.

But the report says the implementation of the law is flawed and said there is no sign that Shell is trying to comply with the law.

The company has not commented on the report but recently released a list of eight cleanup operations it plans to carry out in Nigeria this year, all for spills of less than 100 barrels of oil.

Emmanuel Afimia, founder of Enermics Consulting, said Nigerian authorities must take the Shell divestment plan seriously.

"Nigeria should implement the following measures: establish a robust regulatory framework that holds multinational corporations accountable for the environmental damage caused by their operations; ensure that affected communities are consulted and involved in the cleanup process and that their concerns and needs are addressed," said Afimia. "We need to monitor and evaluate the cleanup process regularly to ensure that it is being done properly and transparently."

VOA asked Nigeria's National Oil Spill Detection and Response Agency for comment on the Shell issue but has not received a response.

Before Shell can sell the assets in question, it must get approval from the Nigerian government. The government has not said whether it will authorize the sale.