BEIJING California said it would cooperate with China on clean technology, emissions trading and other "climate-positive" efforts in a bid to fill a gap left after U.S. President Donald Trump pulled out of the Paris climate accord last week.
The government of California and China's Ministry of Science and Technology will work together to develop and commercialize know-how on carbon capture and storage, clean energy, and information technology to rein in greenhouse gases, according to a Tuesday statement.
President Trump's announcement of the pull-out from the 2015 Paris agreement on climate change was branded as "insane" by California governor Jerry Brown, who was visiting China this week.
The withdrawal decision was seen to have handed the political and diplomatic initiative to China, which has continued to pledge its unqualified support for the accord.
The failure of leadership by the United States was "only temporary", Brown told reporters on the sidelines of a clean energy forum in Beijing on Tuesday, adding that science and the market would be required to get past it.
U.S. Secretary of Energy Rick Perry, who was at the same conference, declined to take questions from reporters.
In an earlier speech, Brown had criticized those still "resisting reality".
"The world is not doing enough," he said. "We are on the road to a very negative and disastrous future, unless we increase the tempo of change."
Brown later met Chinese President Xi Jinping, who urged California to "play a bigger role in promoting exchanges and cooperation between China and the United States", state news agency Xinhua said.
Joint pledges by China and the United States ahead of the Paris talks helped create the momentum to secure a global agreement, and included a promise by China to set up a nationwide emissions trading exchange by this year.
Brown told Reuters last week that he would discuss linking China's carbon trading platforms with California's, the biggest in the United States.
However, China's priority is to focus on its own carbon market "which is big enough and complex enough", Ma Aimin, of the National Centre for Climate Change Strategy and International Cooperation, told the same energy forum.
"Despite China discussing for a long time about linking up with foreign markets, they are still at the stage of talking about it," added Ma, a deputy director general of the body, which is backed by the Chinese government.
"It will be a long time before there is true cooperation with California, whose market is just at a regional stage and is hard to link up with the Chinese market."
(Reporting by Michael Martina; Additional reporting by Muyu Xu, Jake Spring and Chen Aizhu; Writing by David Stanway; Editing by Lincoln Feast and Clarence Fernandez)