The United States President, Joe Biden, spoke to his Chinese counterpart, Xi Jinping, to voice concern about human rights abuses in Xinjiang, where there has been a harsh crackdown on Muslim minorities.

Biden expressed “fundamental concerns about Beijing’s coercive and unfair economic practices,” the White House said in a statement on Wednesday.

In the pair’s first phone call since Biden took office last month, the US president also broached China’s “crackdown in Hong Kong … and increasingly assertive actions in the region, including toward Taiwan,” according to a statement.

In turn, China’s president warned him against a “confrontation” that “is definitely disastrous for both countries and the world,” Chinese state news agency Xinhua reported.

China’s president countered that Hong Kong, Taiwan, and Xinjiang were “China’s internal affairs” and related to its sovereignty and territorial integrity, as quoted by Xinhua news agency.

“The US should respect China’s core interests and act cautiously,” he reportedly said.

The two leaders reportedly exchanged views on countering the coronavirus pandemic, and the shared challenges of global health security, climate change, and preventing weapons proliferation.

Biden also advocated for a “free and open Indo-Pacific.”

China claims almost the entire South China Sea, a key shipping lane believed to be rich in marine and mineral resources.

It has built artificial islands with military-capable facilities over disputed reefs and outcrops in the area.

The US has been advocating for navigation freedom in the disputed maritime area and has conducted navy and military drills there.

According to Xinhua, Xi also advocated “restoring” the various channels of dialogue between the two countries to promote better understanding and avoid misunderstanding.

In addition to diplomatic channels, China’s president also cited an expansion of contacts in business, finance, law enforcement, and between the two armed forces.

Taiwan’s Presidential Office spokesperson Xavier Chang said in a statement that “we admire and thank President Biden for his concerns on the security across the Taiwan Strait and issues about human rights.”

Chang stressed that Taiwan would continue collaborating with like-minded nations, including the US, to contribute efforts to the Indo-Pacific region’s stability and prosperity.

Taiwan’s foreign ministry spokeswoman, Joanne Ou, said on Thursday that the Biden administration had shown its firm support for Taiwan since the inauguration on January 20.

Ou said that the two sides would deepen collaborations in a range of areas, including politics, economy, and security, citing a Wednesday meeting in Washington in which Taiwan’s US envoy Bi-Khim Hsiao exchanged views on issues of mutual interest with U.S. Asia Pacific acting Assistant Secretary, Sung Kim.