The former governor of Papua New Guinea's Madang province, Sir Arnold Amet, has renewed his call for the government to cancel sea bed mining licenses.
This comes as Canadian miner Nautilus, in which the PNG government has a 15 percent stake, is fighting through the courts for its economic survival.
Sir Arnold said he feared that Nautilus, which had been close to beginning sea bed mining at its Solwara One site in the Bismarck Sea, could on sell its PNG licenses.
The James Marape government is backing the call made by Pacific Forum leaders for a 10 year moratorium on seabed mining, but Sir Arnold said it must go further.
"Our preference is, quite obviously, for cancellation of those licenses and a total ban until such time as science can truly satisfy us that that [seabed mining] is worthwhile and economically and environmentally sustainable project. At the moment there is no such evidence," Sir Arnold said.