The U.S. and Japan have pledged a collective $4.5 billion to the Green Climate Fund, an initiative that helps developing countries reduce greenhouse gas emissions. The announcement was made Saturday, the first day of the two-day Group of 20 Summit in Australia. The U.S. pledged $3 billion to the fund while Japan committed $1.5 billion.

U.S. President Barack Obama announced the pledge in a speech to Australian students. Germany, France and other countries also have committed to the fund.

“Along with the other nations that have pledged support, this gives us the opportunity to help vulnerable communities with an early warning system, with stronger defenses against storm surge, climate resilient infrastructure, to help farmers plant more durable crops,” Obama was quoted as saying in a press release by the Green Climate Fund. The fund will help “leapfrog some of the dirty industries that powered our development, go straight to a clean energy economy that allows them to grow, create jobs, and at the same time reduce their carbon pollution,” he added.

The White House said the U.S.-Japan announcement “builds on a history of collective leadership” between the two countries on climate change, pointing out the U.S. and Japan helped create the Climate Investment Funds, a financing organization with goals similar to the Green Climate Fund, in 2008.

“Our pledges to the GCF are a continuation of that spirit of leadership,” the White House said. “The GCF will mobilize investment from the private sector, whose resources and expertise will be essential to meet the climate challenge.”

Héla Cheikhrouhou, executive director of the Green Climate Fund, said the American commitment “will be a legacy of U.S. President Barack Obama. It will be seen by generations to come as the game-changing moment that started a scaling-up of global action on climate change, and that enabled the global agreement.”

The U.S.-Japanese announcement came a week after Obama and Chinese President Xi Jinping reached a climate change deal for both countries to reduce their carbon emissions after 2020. While environmentalists hailed the deal, Republicans in Congress criticized it. Senate Minority Leader Mitch McConnell, R-Ky., who represents a state whose residents are dependent on coal jobs, called the agreement an “unrealistic plan” that “would ensure higher utility rates and far fewer jobs,” according to the Washington Post.  

Obama's visit to Australia wasn't strictly business. The president snuck in a photo-op with Jimbelung, a 2-year-old koala: