Prime Minister Kevin Rudd has moved to reassure the coal and liquefied natural gas (LNG) industries that his government is committed to finding solutions to reducing their carbon emissions.

He also refused to rule out free carbon permits for the LNG sector, saying he is open to submissions on Labor's recent green paper.

"We'll be consulting with the LNG industry extensively across the country and we are confident we can find a way forward on this," he said.

The green paper has proposed that trade-exposed energy-intensive industries be given free permits for a proportion of their emissions.

But this would only apply to existing companies and Woodside Petroleum chief Don Voelte has said two major LNG projects, worth more than $60 billion, could be shelved.

Asked if he would consider free permits for the industry, Mr Rudd replied: "We are looking for submissions from the industry on the specific data requirements we have."

Mr Rudd was speaking in Darwin, which is hoping to win over Japanese oil and gas giant Inpex in the battle against Western Australia for a $12 billion LNG plant.

The prime minister refused to be drawn on which site had his backing.

"Ultimately, this is a project for the nation," he said.

NT chief minister Paul Henderson, who earlier this week used the gas plant as a mandate for an early election, conceded there were concerns within the LNG sector but he was confident they could be resolved.

"It is an opportunity for Australia to grow an industry that is really going to contribute to a reduction of greenhouse gases globally," said Mr Henderson, who heads to the polls on August 9.

Mr Rudd said the LNG challenge was threefold: continuing its role within the economic future of Australia, expanding the industry as a green-friendly energy and reducing its emissions.

"And you know what, you can do all three things," said Mr Rudd.

There was also a viable role for coal-fired energy in Labor's vision for a green-friendly Australia, he said.

"Of course it has a future, that's why we are engaged very much with the industry on the support they will need for their adjustment processes."

Mr Henderson, now into day three of a 19-day election campaign, dismissed the suggestions that an Inpex project in Darwin would drive up local rental prices and ultimately rely on fly-in workers.