DARYL PASSMORE | The Courier-Mail
"This asset could be worth in excess of $US35 billion," Mr Palmer said.
The discovery could rival the North West Shelf in Western Australia, he claimed.
The tenement in the Gulf of Papua is 100% owned by Palmer Petroleum, the oil and gas division of the billionaire's Mineralogy group.
Mr Palmer said he had spent more than $50 million exploring the area so far.
"The results of the studies are extremely favourable," he said.
"This is an exciting development for the Papua New Guinea economy and the region."
Mr Palmer said while the likely current value of the deposit was $35 billion, it would be many times that once in production.
It would take many years and up to $20 billion of investment to reach that stage.
"There are plenty of people who want to invest in oil and gas," he said.
"The world is hungry at the moment for gas for environmental reasons.
"It's certainly much bigger than any gas development undertaken in Australia," Mr Palmer said.
Future royalties would help PNG become more self-sufficient and "it will help my pocket".