By Patricia Zengerle and Michael Martina

WASHINGTON (Reuters) -President Joe Biden’s nominee to be U.S. ambassador to China, Nicholas Burns, took a tough line on dealings with China at his Senate confirmation hearing on Wednesday, saying “genocide in Xinjiang,” abuses in Tibet, and bullying of Taiwan must stop.

Burns, calling China the United States’ “most dangerous competitor”, said Beijing is “blasting past” its pledge to maintain only a minimum nuclear deterrent, and added that Washington should work with allies in Europe and elsewhere to build economic leverage.

Human rights advocates and the U.S. government have termed China’s treatment of Uyghur Muslims in its Xinjiang region “genocide,” a characterization that China rejects.

“The PRC’s genocide in Xinjiang, its abuses in Tibet, its smothering of Hong Kong’s autonomy and freedoms, and its bullying of Taiwan are unjust and must stop,” Burns said, using the acronym for the People’s Republic of China.

Burns, 65, a career diplomat and former ambassador to NATO, also said Washington is correct in adhering to its current “One China” policy on Taiwan, but right to oppose actions from Beijing that undermine the status quo.

Some lawmakers, including some of Biden’s fellow Democrats, have called for Washington to revisit the decades-old policy, which takes no position on Taiwan’s sovereignty.

Burns said China’s military threat to Taiwan was growing, but that maintaining the One China policy was the smartest and most effective way to deter China from exercising force over the self-ruled democratic island.

“This is a policy that can succeed if we execute it consistently and with some strength,” Burns told the Senate Foreign Relations Committee, adding that the most important deterrent was for the United States to maintain its military standing in the Indo-Pacific.

Still, he said Congress and the executive branch had every right to “expand our arms provisions to Taiwan.”

Burns is expected to easily win confirmation, earning praise from members of both parties. “It is, I think, appropriate that Ambassador Burns was appointed to this position,” said Senator Jim Risch, the committee’s top Republican.

Burns also discussed at some length his view that China is relatively isolated internationally.

“The Chinese are being so aggressive, they have stirred up a lot of opposition to them. And I think we ought not to exaggerate their strengths, or underestimate the strengths of the United States,” Burns said.

He said Beijing had been “stonewalling” the world about the origins of the coronavirus.

“We need to investigate. We don’t know how this virus originated for sure, there are multiple theories and the Chinese need to answer the questions,” Burns said.

China’s embassy in Washington did not respond immediately to a request for comment on Burns’ remarks.

‘REAL LEVERAGE’

Burns said that unlike during the Cold War, U.S. competition with China would revolve around economic and technological might, not military capabilities.

He said the United States was right to hold Beijing to its “phase one” trade deal commitments, and urged Congress to pass languishing China-related legislation intended to fund U.S. domestic competitiveness in critical sectors, such as semiconductors.

“It may be the most important thing we can do — is to invest in our technological future, as the Senate is doing with your strategic innovation bill, which the administration very strongly supported. And I do too,” Burns said.

Joining with the European Union and Japan on economic issues would provide “real leverage” over China, he added.

He was asked about the Winter Olympics in Beijing in February, but did not directly address some calls for a boycott of the games over human rights issues.

Due to China’s COVID restrictions, the Olympics were likely to be the “most unusual games ever” in that few foreign spectators were expected, he said.

“We obviously want to make sure that the American athletes … are able to speak their minds, are able to have access to the media, to say what they wish to say,” Burns said. “And I hope and trust that the International Olympic Committee will make that possible.”

(Reporting by Michael Martina and Patricia Zengerle; Editing by Sandra Maler and Alistair Bell)

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