US Treasury Secretary Janet Yellen urged China on Saturday to combat the “existential threat” of climate change by supporting international funds intended to help developing countries confront the crisis. On the second full day of her visit to Beijing, Yellen said the United States and China should work together to tackle global challenges despite differences over a range of issues. “As the world’s two largest emitters of greenhouse gases and the largest investors in renewable energy, we have both a joint responsibility — and ability — to lead the way,” she told a group of officials and climate experts. “Climate change is at the top of the list of global challenges, and the United States and China must work together to address this existential threat.” Yellen is visiting the Chinese capital as it grapples with what is shaping up to be one of the most severe heat waves on record. Beijing’s temperature soared past 40 degrees Celsius (104 degrees Fahrenheit) again on Thursday. Since 1951, Beijing has seen temperatures rise above 40C (104F) on 11 days, and five of them occurred over the past two weeks. Globally, this week saw the hottest temperature ever recorded, according to data from two climate tracking agencies that covers multiple decades. The previous record was set in August 2016. Yellen said China’s support for existing multilateral climate institutions like the Green Climate Fund (GCF) and the Climate Investment Funds, alongside the United States and other partners, could improve their impact. The GCF is the main climate financing mechanism of the United Nations and helps developing countries to tackle climate change. In April, US President Joe Biden pledged a $1 billion contribution to the GCF and a $500 million investment to the Amazon Fund, an international conservation program to protect the Amazon rainforest from deforestation. Last year, China suspended climate talks with the US and took other countermeasures in response to then-US House Speaker Nancy Pelosi’s visit to Taiwan in August. Attending the climate roundtable event with Yellen in Beijing, US Ambassador to China Nicholas Burns described her first day of meetings as “very productive.” He said he was looking forward to a visit by US climate envoy John Kerry but did not provide a timetable for the trip. Kerry would be the third Cabinet official from the Biden administration to travel to China, after Yellen and Secretary of State Antony Blinken, who visited in June.