Queensland billionaire Clive Palmer has signed a deal to sell millions of tonnes of coal to China in what's believed to be Australia's largest export contract.

Mr Palmer says the $69 billion, 20-year offtake deal was signed last Friday with China Power International.

Another $8.6 billion agreement was signed with the Metallurgical Corporation of China to build the project in central Queensland.

Mr Palmer's Resourcehouse wants to develop a 40 million-tonne-a-year thermal coal mine in the Galilee Basin, near Alpha, west of Emerald.

"That's the biggest coal mine in the world in one go I think you'll find," Mr Palmer said.

"This is really a great time for the state.

"You know, things have been a bit quiet lately and it's good to see that we can revitalise the economy."

Queensland Premier Anna Bligh says the project will boost the state's economy.

"What the signing of this contract with the Chinese company means is that Australia's largest single export deal ever signed will be happening right here in Queensland," Ms Bligh said.

Four underground mines and two open cut mines will be developed, as well as a new coal port at Abbot Point, near Bowen.

A new 500 kilometre rail line will be built to link the mine and the terminal.

Jobs target

Mr Palmer says the project will create jobs.

"It'll create 7,000 jobs, I believe during construction and operations, and they'll be direct jobs," he said.

Ms Bligh says it helps reach her election promise to create 100,000 new jobs.

"We've already seen 30,000 jobs created in the last couple of months." she said.

"We still have some 98,000 jobs to go to reach that target, because for some time last year we went backwards."

Differences aside

Mr Palmer is suing the Queensland Premier over comments she made about his links to the Liberal National Party.

He is a large financial backer of the party but he says they have put their differences aside for the project.

"You've got to understand the Premier is a very compassionate, caring person who cares about the future of Queenslanders and about jobs," he said.

But he is still suing Ms Bligh.

"Life's got to be interesting hasn't it," he said.

Ms Bligh says the defamation suit will be solved by lawyers.

"But neither Mr Palmer or I are going to let any of those issues get in the way of jobs for Queenslanders," she said.

The State Government could reap up to $500 million a year in royalties, dependent on the price of coal.

"That is a huge boost and a massive shot in the arm for the Queensland economy and it's great news for central Queensland and regional Queensland," Ms Bligh said.

The mine is expected to be fully operational by 2014.