Papua New Guinea's opposition wants the Ombudsman to investigate a recent court judgement which awarded a state payment of around $US60 million.
The payment was awarded to the Mineral Resources Development Corporation and a landowner company (Petroleum Resources Gobe) over reportedly unpaid oil development royalties for landowners.
The Attorney-General Davis Steven said the award was granted after State lawyers failed to defend the case, and subsequently sacked the Solicitor-General.
However, opposition leader Patrick Pruaitch has raised suspicion over the case because he says the Corporation is a quasi-government entity, whose chairman is the government's Chief Secretary and which reports directly to the Prime Minister.
Mr Pruaitch said it was an internal government matter that should not have ended up in the courts, and he said there were no outstanding royalty claims.
According to him, there were many elements in the case that deserve scrutiny by the Ombudsman Commission in terms of the Leadership Code
The former Treasurer said in the first instance it was inexplicable that the Corporation should make a claim on behalf of Gobe landowners over reportedly outstanding royalty payments.
Furthermore, "the court proceedings make it clear that there are no outstanding royalty claims by MRDC and/or the landowners against Oil Search Ltd, which has been paying due royalties since the Gobe oilfield was developed in the 1990s".
All such funds are either held in trust or passed on to Petroleum Resources Gobe, according to Mr Pruaitch.
"Prima facie the default judgement has all the elements of a potential case of collusion between various persons in leadership positions to defraud the State, an issue that can only be laid to rest by a thorough investigation by the Ombudsman," he said.