Yellen's meeting with Chinese Vice Premier Liu He, to take place in Zurich, will be their first in-person encounter following three virtual meetings, the official said.

In an interview on National Public Radio on Saturday, 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 US 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 also expected to touch on the debt issue and other significant differences between the two nations.

US President Joe Biden and his Chinese counterpart Xi Jinping had vowed during a November meeting in Bali, Indonesia to improve communications after years of sharp tensions over trade, human rights, Taiwan and other issues.

Yellen and Liu will "exchange views on macroeconomic developments and other economic issues as well as deepen communication" between their countries, the Treasury official said. 

In Bali, Biden and Xi had pledged "to continue responsibly managing the competition between our two countries and to explore potential areas of cooperation," the State Department said in November.

Weeks later, a first high-level US delegation -- led by Assistant Secretary of State for East Asian and Pacific Affairs Daniel Kritenbrink and the National Security Council director for China and Taiwan, Laura Rosenberger -- traveled to China for follow-up talks.

That delegation was also there to prepare a visit early this year by US Secretary of State Antony Blinken, to be the first by the top US diplomat in four years.

The United States and China -- the two largest economies in the world -- spend more than any other nations on their militaries and are locked in fierce strategic competition. 

In their Bali meeting, the two leaders discussed contentious issues, including Taiwan's future, US restrictions on Chinese high-tech imports and China's moves to expand its global influence.

Long-simmering disputes between the two countries flared during the Donald Trump presidency, and have continued -- if less acutely -- under President Biden.

Both Biden and Xi have said they want to reduce tensions.

Biden left his Bali meeting with Xi proclaiming that there need not be a new Cold War, while Xi told the American president that the two countries "share more, not less, common interests."