U.S. Treasury Secretary Janet Yellen will visit Chinese Vice Premier Liu He in Switzerland on Wednesday to discuss recent economic events and improve relations between the two largest economies in the world, according to a Treasury official.

Following President Joe Biden’s discussions with Chinese President Xi Jinping in Indonesia in November, both countries agreed to cooperate to reduce tensions, and Yellen and Liu will now meet in person for the first time.

Yellen will meet Liu in Zurich on the eve of her three-country visit to Africa, where she will focus on strengthening U.S. ties with a continent that has long been the focus of Chinese trade and investment, and issues such as food security.

China’s foreign minister, Qin Gang, is just wrapping up five-country tour of Africa, the 33rd consecutive year that Africa has been the destination of the Chinese foreign minister’s first overseas tour of the calendar year.

In an interview aired Saturday on National Public Radio, Yellen acknowledged that China had played “a leading role” in lending to and trading with African nations, but said African leaders had made clear at a conference last month in Washington that they were seeking more U.S. engagement.

“It’s clear that they want to expand trade and investment with many parts of the world and see the United States as a critical partner in that growth. And that’s something that’s important to us as well,” Yellen said.

Chinese trade with Africa is about four times that of the United States, and Beijing has become an important creditor by offering cheaper loans – often with opaque terms and collateral requirements – than Western lenders. But some African countries, including Zambia, have soured on Chinese lending and are looking for alternatives, economic analysts said.

Yellen’s meeting with Liu is expected to touch on the debt issue and other significant differences between the two nations.

Yellen has repeatedly criticized Beijing – now the world’s largest creditor – for not moving more quickly to restructure the debt of poor countries in Africa, and often raises concerns about forced labor used in China’s Xinjiang province.

In July, when she spoke with Liu by phone, Treasury said she also spoke “frankly” about the impact of Russia’s war against Ukraine on the global economy, and China’s “unfair, non-market” economic practices.

Liu is in Switzerland for the World Economic Forum meetings in Davos, which Yellen does not plan to attend. Other senior U.S. officials will represents Washington there, including U.S. Trade Representative Katherine Tai and climate envoy John Kerry.

Yellen has met virtually three times with Liu since taking office, and met in Bali with Chinese central bank governor Yi Gang. Liu will step down this year as part of an overhaul of China’s economic leadership disclosed in September.

In December, the former Federal Reserve chair told reporters she was also open to visiting China and looked forward to more “intense interactions” with Chinese officials than in the first two years of Biden’s four-year term.