The fund, which one of the people described as the largest such effort in history, is meant to pay for research and development of new clean-energy technologies. It will include contributions from other billionaires and philanthropies, as well as a commitment by the United States to double its budget for clean energy research and development, according to the people with knowledge of the plans. French government sources also confirmed the launch plans.

The announcement of the Clean Tech Initiative fund, which has the joint backing of the governments of the United States, China, India and other countries, the people said, is intended to give momentum to the two-week Paris climate talks.

Negotiators hope to strike a deal committing every nation to enacting policies to reduce fossil fuel emissions. Mr Gates, co-founder of Microsoft, will join more than 100 world leaders, including President Obama, in Paris on Monday to begin the talks.

The pending announcement was first reported by ClimateWire, an online news organisation. A spokesman for the Bill and Melinda Gates Foundation did not respond to a request for comment.

Fundamental shift

If successful, the Paris meeting could spur a fundamental shift away from the use of oil, coal and gas to the use of renewable energy sources such as wind and solar power. But that transition would require major breakthroughs in technology and huge infrastructure investments by governments and industry.

Where that money would come from has been a question leading up to the Paris talks. Developing countries like India, the third-largest fossil-fuel polluter, have pushed for commitments by developed nations to pay for their energy transition, either through direct government spending or through inexpensive access to new technology.

India has emerged as a pivotal player in the Paris talks. The announcement by Mr Gates appears intended to help secure India's support of a deal.

As US secretary of state, Hillary Clinton pledged that developed countries would send $US100 billion ($139 billion) annually to poor countries by 2020 to help them pay for the energy transition. Indian officials have demanded that the Paris deal lock in language that the money would come from public funds — a dealbreaker for rich countries.

This summer, Mr Gates pledged to spend $US1 billion of his personal fortune on researching and deploying clean energy technology, but the people with knowledge of his plans said the new fund would include larger commitments.

In a blog post in July, Mr Gates wrote: "If we create the right environment for innovation, we can accelerate the pace of progress, develop and deploy new solutions, and eventually provide everyone with reliable, affordable energy that is carbon free. We can avoid the worst climate-change scenarios while also lifting people out of poverty, growing food more efficiently and saving lives by reducing pollution."

New solutions

Mr Gates met with Prime Minister Narendra Modi of India in September on the sidelines of the United Nations General Assembly meeting in New York. In a June meeting in Paris, Mr Gates told President François Hollande of France that the Paris deal should include robust provisions on clean energy research and development.

"Bill's been making that point for years, and he's going to make it more emphatically in Paris," said Hal Harvey, chief of Energy Innovation, an energy consultancy.

Mr Harvey noted that at the core of the emerging Paris agreement are plans and pledges already put forth by more than 170 countries detailing how they will reduce emissions.

"If you tote up the plans, you see a very significant demand signal, and Bill wants to see that we meet that cheaply," he said.

The New York Times with Reuters