Amazon chief executive Jeff Bezos on Monday said he would commit $10 billion (Dh36.73bn) to fund scientists, activists, charities and other groups fighting to protect the environment and counter the effects of climate change.
The Bezos Earth Fund, which aims to fund “any effort that offers a real possibility to help preserve and protect the natural world”, will begin issuing grants this summer.
"Climate change is the biggest threat to our planet," Mr Bezos wrote in an Instagram post.
"I want to work alongside others both to amplify known ways and to explore new ways of fighting the devastating impact of climate change on this planet we all share.
"It's going to take collective action from big companies, small companies, nation states, global organisations and individuals," Mr Bezos said.
The world's richest man, with a fortune worth about $130bn, he is among a growing list of billionaires to dedicate considerable funds to battle the effect of global warming.
Counteracting climate change has become a popular cause for US billionaires in recent years, with Microsoft's Bill Gates, Michael Bloomberg and hedge fund manager Tom Steyer among the world's wealthiest environmental philanthropists.
Last year, Mr Bezos pledged to make online retailer Amazon net carbon neutral by 2040, making it the first major corporation to announce such a goal.
He also said he would buy 100,000 electric delivery vehicles from US vehicle design and manufacturing start-up Rivian Automotive.
Mr Bezos said Amazon would meet the goals of the Paris climate accord 10 years ahead of the accord's schedule and invest $100 million to restore forests and wetlands.
But environmental activists have long criticised his company for its significant impact on the environment.
Amazon delivers 10 billion items a year and has a massive transport and data centre footprint. The company has also faced criticism from within its own workforce.
The e-commerce giant has faced protests by environmental activists and pressure from its employees to take action on climate change, which were inspired by Swedish teenager Greta Thunberg.
Amazon staff joined hundreds of employees of big technology companies in climate-change marches in San Francisco and Seattle last year, saying their employers had been too slow to tackle global warming and needed to take more drastic action.
Amazon was embroiled in further controversy after a report by The Guardian revealed last month that it had threatened to fire employees for speaking publicly about the company's role in the climate crisis.
Amazon Employees for Climate Justice, an activist workers group, welcomed the Bezos Earth Fund announcement, but said it did not make up for the company's consumption of fossil fuels and other activities that contribute to climate change.
"We applaud Jeff Bezos' philanthropy but one hand cannot give what the other is taking away," the group wrote on Twitter.