SACRAMENTO, Calif. – California Gov. Jerry Brown will travel to China to discuss clean energy policy with international leaders next month, his office announced Friday.

He’ll attend an international energy conference in Beijing with delegates from nearly two dozen countries during his visit during the first week of June.

He will also visit Chengdu in Sichuan province and Nanjing in Jiangsu province during the weeklong trip. Both provinces are, along with California, part of the Under2 Coalition of regions that have pledged to limit global warming to below 2 degrees Celsius (3.6 degrees Fahrenheit).

Brown’s office says the trip will strengthen California’s climate, clean energy and economic ties with China. The Pacific Rim county is the world’s top carbon polluter. The United States generates the second-largest amount of carbon pollution.

Combatting climate change is one of the governor’s signature issues. He has led California to adopt some of the most ambitious anti-pollution policies in the United States, even as President Donald Trump’s administration in Washington works to boost the U.S. coal industry and threatens to pull out of the Paris climate accord.

China is now outpacing the U.S. in transitioning to cleaner energy sources.

Brown’s efforts to strengthen ties with China also put him at odds with Trump, who has historically been critical of the country.

Brown previously visited China in 2013 on a trade policy trip.

In recent years, the governor has also travelled to France, Italy, Canada and Mexico for climate change talks.