Fearing a nascent global climate accord could be strangled at birth by sceptical US Republicans, President Barack Obama is wooing an unlikely ally -- big business.

Obama has spent the months ahead of crunch talks in Paris starting on November 30, setting out the moral, political and economic case for tackling climate change.

On Wednesday in Manila, Obama renewed that push, urging a forum of influential Asia-Pacific CEOs to get behind the accord, which aims to reduce the greenhouse gas emissions that are blamed for global warming.

"An ambitious agreement in Paris will prompt investors to invest in clean energy technologies because they will understand that the world is committed to a low-carbon future," Obama said.

"That's a signal to the private sector to go all-in on renewable energy technologies."

It is just the latest White House effort to woo companies and get big name CEOs to lend their political support to the deal.

At the White House in October, Obama hosted CEOs from Intel, Johnson & Johnson and some of the 81 companies that have signed up to a climate pledge.

But the White House drive is about more than moral support, it's about creating political facts on the ground.

The White House is betting that having corporate support will make new rules more difficult to overturn and position climate-denying Republicans in an uncomfortable position in opposition to their traditional allies.

"If you look at the history of environmental regulation, rules that are put in place that go with the grain of where the industry is headed very rarely get scrapped or completely overturned," said a senior administration official.

"When they become embedded in the structure of the sector in which they operate you actually create long-term incentives that the private sector responds to, and they become part of the structure of our economy."

- History repeating? -

Administration officials point to the experience of fuel economy standards.

That "offered companies long-term certainty -- instead of states setting" a multitude of disparate rules.

In the White House and among US allies there is a perennial concern that US commitment to a deal could be gutted after the 2016 election.

Two decades ago Bill Clinton, a second term democratic president agreed the Kyoto Protocol in the twilight of his administration.

Within months, Republican victor George W. Bush had shredded the agreement and along with it US credibility on climate change.

Obama could find himself in much the same position as Clinton did before Kyoto was agreed.

On Tuesday the Republican-run US Senate rejected key rules wanted by Obama's administration to limit greenhouse gas emissions by power plants.

But business may lend a hand.

During seven years in the White House, Obama has had a vexed relationship with the titans of commerce.

Big banks railed against his Wall Street reforms in the wake of the 2008 financial crisis and the US Chamber of Commerce has painted him as a big government leftist.

But on climate, there are signs that interests may converge.

According to a recent UN-Accenture study, 70 percent of executives at companies with revenues of over $1 billion a year see climate change as an opportunity for growth and innovation.

If firms buy in to long-term climate targets and manoeuvring their business as a result, Republicans risk being seen as threatening much-vaunted "business certainty."