Dodgy lawyers have siphoned off as much as 1 billion kina (about $A425 million) from PNG's public coffers, the country's attorney-general says.
Kerenga Kua has told a law seminar in Port Moresby lawyers are using their skills and education to rip off the country.
"I don't want to pick figures out of the blue," the National reported him as saying on Friday.
"I think in the last six years or so, lawyers would have been involved and assisted in committing fraud against the state that could be easily estimated to be close to kina 1 billion."
Mr Kua was speaking on the subject of ethics and court etiquette at the PNG Law society.
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He said some of PNG's 1100 registered lawyers were failing the rules of ethical or professional conduct.
Mr Kua was until 2012 a principal lawyer in law firm Posman, Kua, Aisi Lawyers.
He played a key roll in the 2011/12 political turmoil in PNG, representing the ousted government of Sir Michael Somare in court.
After the 2012 election, he was appointed attorney-general by his one-time legal opponent, Prime Minister Peter O'Neill.
Mr Kua said the fight against corruption in PNG is going slowly because of a lack of resources.
"We cannot move on everybody because of the limited resources and skills that are available to the government," he said.
He added the government will act in the coming weeks and months to clean up the legal landscape.
"All the talking has got to come to a stop one day," he said.
Mr Kua's comments come just weeks after secretary to the government Theo Zurenouc told an anti-corruption forum in PNG's second largest city, Lae, the government was preparing to table legislation for an independent commission against corruption.
Mr Kua has also stated he wants the commission to have teeth and be able to follow cases through to prosecution "for better or for worse". The head of the government's anti-corruption watchdog Taskforce Sweep, Sam Koim, recently revealed as much as 40 per cent of public funds is squandered or lost to corruption annually.
In 2010, then-prime minister Sir Michael Somare tabled a commission of inquiry report into PNG's department of finance, which he said would make readers "shudder in awe" at the level of corruption revealed.
The report made 75 recommendations after revealing half a billion kina had been spent on questionable deals.
The day after Sir Michael tabled the report, the court placed a ban on its publication and implementation, following a challenge by former solicitor-general Zachery Gelu and lawyer Paul Paraka.
That injunction is now being challenged in the courts.
