Amazon's Jeff Bezos pledges $10bn to fight climate change
"Climate change is the biggest threat to our planet," Mr Bezos said 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."
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.
"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 substantial funds to battle the impact 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 startup Rivian Automotive.
Mr Bezos said at the time that 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.
It 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.
Amazon 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 late last year, saying their employers had been too slow to tackle global warming and needed to take more drastic action.
The company 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 Amazon’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 said on Twitter.