Climate Change Minister Greg Combet says he will likely release details of the Federal Government's carbon tax in July.

Mr Combet this morning told ABC Radio he will be "working pretty hard over the course of the next two months to produce the detailed package".

"There's a lot of work still ahead of us. We've got to argue the case in the community but also do the detailed policy work," he said, adding July is within the timeframe.

But the Government is still struggling to convince voters of the merits of its proposed carbon tax, according to the latest Newspoll.

Two-and-a-half years ago support for Kevin Rudd's emissions trading scheme was running at 72 per cent.

Just after Prime Minister Julia Gillard announced a carbon tax in February, breaking an election pledge, support fell to 42 per cent.

But today's poll has found just 30 per cent of voters support the carbon price - which will come into effect next year - while 60 per cent are against it.

Newspoll spokesman Martin O'Shannessy says what remains consistent is strong community belief in climate change and that human activity plays a part.

"What we're seeing is, I think, people expressing their natural concern or doubt or reticence to support something that hasn't been fully explained to them yet," he said.

"I think they're against what's being offered so far."

Mr Combet pledged to continue to argue the case for a carbon tax.

"Putting a price on carbon so we can cut pollution and drive investment in clean energy is the right policy response. It will cut pollution. It will drive investment in clean energy.

"And in doing so the Government has committed a very considerable part of the income from the tax to assist households."

Opposition Leader Tony Abbott's anti-carbon tax crusade is paying off and there are plenty more potential backdrops for his campaign.

But Mr O'Shannessy says it is still early days.

"If we go back to 2001 after the introduction of the GST, John Howard was in negative territory quite deeply for about six months," he said.

Ms Gillard is hosting a dinner tonight for a select group of business leaders in an attempt to breathe fresh life into negotiations on the tax.

Support is fractured, with big business demanding more generous compensation than under Mr Rudd's emissions trading scheme.

More meetings are scheduled for tomorrow as the trade-exposed sectors watch the dollar soar to new heights.

The Government does not plan to name the carbon price for another month or two, but even those who support the tax say it is not a great time to take on a new burden.

The business leaders will dine with Ms Gillard at Kirribilli House, but Nationals leader Warren Truss thinks it will take a triple round of after-dinner drinks for business leaders to go home with any sense of well-being.

"I hope big business isn't simply beguiled with magnificent menus and harbour views and fine wines," he said.

"I hope [they] experience enough in life not to be so easily bought off.

"No families have been invited. No small business. And yet these are the people who will be paying the power bills, who will have extra prices for their food and their petrol and other costs."

Mr Combet says big reforms require the Prime Minister to talk to the business community.