The treatment of half a million litres of waste oil discharged by P&O Cruises near Vanuatu's capital Port Vila has been put on hold.
Vanuatu's Quarantine Department has put the process on hold because of concerns that the chemical to be used to treat the waste sludge is environmentally dangerous itself.
The disposal of the environmentally hazardous waste late last year triggered outrage among locals and prompted P&O to conduct a remediation plan.
The plan involved engaging environmental experts from New Caledonia to come and contain the sludge before carrying out on-site treatment of the waste.
But the president of Shefa Provincial Council, John Markal, says not all of the sludge has been contained.
"I'm really concerned about this. We have a group of consultants who are carrying out research and investigation, and we are pushing for a claim for compensation through the international convention - the Maritime convention."
The president of Shefa Provincial Council, John Markal