A strong partnership between the US state of California and China has emerged based on friendship and recognition that the Earth's changing climate is a crisis that threatens both of them, Eleni Kounalakis, Lieutenant Governor of California, said Wednesday.

Delivering a speech at the opening ceremony of the 2019 China-California Business Forum, Kounalakis listed California's achievements in recent years in combating climate change and recalled her trip last month to Beijing, where she attended two forums at the Belt and Road Conference as representative of the Golden State.

"I discussed the robust relationship between China and California about combating climate change, and the important role China must play in helping lead the world on this issue," the Greek-American politician told over 500 entrepreneurs and officials from China and California.

She said that since 2013 California had signed several memoranda of understanding with China at national, provincial and municipal levels, saying these documents established a framework for engagement and policy exchange between two sides at different levels, and extended research collaborations.

The partnership was initiated around California sharing the best practices with China to reduce air pollution, including strengthening vehicle pollution standards, promoting environmentally sustainable ports and improving maritime vessel compliance with fuel regulations, she said, adding that both governments had invested billions of dollars in this field.

Kounalakis also disclosed that California helped China to develop a national Cap and Trade program, which is a carbon emissions trading program designed to limit carbon emission while generating substantial revenue.

"We formalized our cooperation through agreements signed with the National Development and Reform Commission, and have been closely engaged with the regional pilot programs," she said, "As you can see, the cooperation between California and China is robust, mutually beneficial and good for world."

Wednesday's forum is a signature event within the framework of China Provinces and US California Joint Working Group on Trade and Investment Cooperation.

More than 70 companies from eight Chinese provincial regions participated in the forum, focusing on topics including clean energy, cross-border e-commerce, investment, manufacturing and innovation.

This year's annual forum makes China's Guangdong Province the Guest Province of Honor. Ouyang Weimin, Vice Governor of the province, also suggested in his speech strengthening cooperation with California in the field of lowering carbon emission and environmental protection.

"In this regard, Guangdong and California already have an established base for cooperation," Ouyang said. "As early as 2013, the then Governor of California, Mr. Jerry Brown, visited Guangdong and both sides signed a memorandum of understanding on strengthening cooperation in terms of low-carbon emission development."

"We hope that both sides will cooperate pragmatically in formulating plans for developing a low-carbon economy, saving energy and improving energy efficiency, and developing clean energy sources," he said.