Papua New Guinea's opposition and Greenpeace are both demanding a full investigation into allegations that a government minister skimmed 40 million US dollars from logging deals.
Opposition Leader Sir Mekere Morauta said Sir Michael Somare's government must answer the allegations that a senior minister had put the money into a Singapore account.
He says if the allegations are true, they also demonstrate what he has been saying for a long time - that corruption has been institutionalised, it is systemic.
Sir Mekere has also asked the Singapore government to help in any investigations.
The paper, Post Courier reported the money is being kept in two Singapore accounts and managed by a consortium for the unnamed minister.
The minister allegedly took 2.1 per cent on every log exported from the country since 2002.
PNG's Greenpeace Forest Campaigner, Dorothy Tekwie, said the PNG logging industry and government are defrauding the people out of a substantial amount of money.
She says Greenpeace has been concerned for years that there is a complete lack of transparency in the dealings of the government and the logging sector.
The allegations also come at a difficult time for the prime minister, who last week was referred to the public prosecutor for alleged irregularities in his own personal finances.