HK GOT INT,L STRATEGIC CONSULTING LIMITED

TAIPEI, Taiwan — President Tsai Ing-wen of Taiwan called on Saturday for domestic and international support of the island’s de facto independence, days after China’s leader, Xi Jinping, warned that unification with China was inevitable.

“It is impossible for me or, in my view, any responsible politician in Taiwan to accept President Xi Jinping’s recent remarks without betraying the trust and the will of the people of Taiwan,” Ms. Tsai said in a briefing for foreign reporters in Taipei, Taiwan’s capital.

“We hope the international community will pay attention and combine efforts to speak out on our behalf,” she said.

Mr. Xi’s speech, his first major address on Taiwan, has given Ms. Tsai a chance to position herself as the young democracy’s defender, both to the outside world and to voters who will decide next year whether she stays in office. Her party was battered in local elections in November, but since Mr. Xi’s address there has been a groundswell of support for her on Taiwan social media and even, to some degree, in publications that tend to oppose her.

Tensions between Taiwan and Beijing, which claims the self-governing island as part of Chinese territory, have emerged as one of the region’s flash points. Mr. Xi, the most powerful Chinese leader since Mao, reiterated in his speech that Beijing would use force if necessary to prevent Taiwan from seeking formal independence.

Mr. Xi has been ramping up pressure on Ms. Tsai’s administration over her refusal to accept the so-called 1992 consensus — a vague notion, accepted by Ms. Tsai’s predecessor, that posits that Taiwan and China are part of the same country, with each side allowed its own interpretation of what that China is.

In his speech, Mr. Xi urged Taiwan to avoid a “dead end” and accept his offer of the “one country, two systems” framework under which Hong Kong has operated since Britain returned it to Chinese rule in 1997.

But many people in Hong Kong and elsewhere — not least in Taiwan, where the situation is closely watched — believe that Hong Kong’s promised freedoms have been eroding under Mr. Xi’s rule.

“I myself expect all of Taiwan’s political parties to clearly state, ‘We reject “one country, two systems,’” Ms. Tsai said on Saturday. “And there’s no need to talk about the 1992 consensus anymore, because this term has already been defined by Beijing as ‘one country, two systems.’”

Analysts said that Ms. Tsai, both on Saturday and in a speech on Wednesday responding to Mr. Xi, had taken an unusually firm, unequivocal posture, marking a shift away from the cautious ambiguity she had previously deployed, apparently in hopes of avoiding unnecessary provocations.

“There is no doubt that Tsai has changed her tone,” said Austin Wang, an assistant professor of political science at the University of Nevada, Las Vegas, who studies Taiwan. “Tsai made a huge shift from not publicly accepting the 1992 consensus to directly rejecting it.”

Taiwan’s opposition Kuomintang party, which once ruled China, moved its government to the island in 1949, having lost the civil war to Mao’s Communists. Taiwan is still formally known as the Republic of China, the name under which the Kuomintang governed the mainland.

The Kuomintang said Thursday that it was opposed to Taiwan independence — a phrase it takes to mean the removal of vestiges of the Republic of China in favor of a Republic of Taiwan.

But even the Kuomintang, which favors closer relations with Beijing than does Ms. Tsai’s Democratic Progressive Party, said after Mr. Xi’s speech that a Hong Kong-style arrangement would not be supported by most Taiwanese.

An opinion article published on Saturday in the United Daily News, a Kuomintang-friendly news outlet, said that Ms. Tsai’s response to Mr. Xi this past week, including several posts on her Facebook page, had reversed her fortunes with much of the public. An essay that has circulated widely on Taiwanese social media portrays Ms. Tsai as a mother vowing to defend her child from a bully.

Ms. Tsai’s more assertive tone is likely to be noticed in Washington. The United States broke ties with Taiwan in 1979 in order to establish full relations with Beijing. But Taiwan at that time had been under martial law for decades, and since it embraced democracy in the 1990s many in Washington have seen it as a like-minded partner, as well as a bulwark against China’s influence.

Calls for the United States to help safeguard Taiwan’s democracy are rising on Capitol Hill, part of a bipartisan pushback against China.

Last month, six senators — three Republicans and three Democrats — sent a letter to Secretary of State Mike Pompeo; Treasury Secretary Steven Mnuchin; the national intelligence director, Dan Coats; and the F.B.I. director, Christopher Wray, asking for an investigation into the Tsai administration’s charges that Beijing tried to subvert the island’s November elections.

“We encourage you to work closely with Taiwan authorities to thoroughly investigate these allegations and, if necessary, take swift action to deter future C.C.P. interference in elections in Taiwan or elsewhere across the globe,” the senators wrote, referring to the Chinese Communist Party.

Concerns that any Chinese attempts to subvert democracy in Taiwan could soon be repeated elsewhere are reasonable, said Lauren Dickey, an analyst at the Center for Naval Analyses in Arlington, Va.

“It merits watching how Chinese tactics toward Taiwan have evolved — and will likely continue to evolve — as a way to analyze how Chinese efforts to coerce or influence may manifest in other countries,” Ms. Dickey said.

Ross Darrell Feingold, a political consultant based in Taipei, said Ms. Tsai’s firm stance toward China was likely to be seen favorably by American officials, in contrast to recent overtures toward Mr. Xi by President Moon Jae-in of South Korea and, to a lesser extent, by Prime Minister Shinzo Abe of Japan.

“The American government, whether it’s the executive or legislative branch, is looking for leaders around Asia who are clear and assertive in their reacting to China’s aggressive behavior in the region,” Mr. Feingold said. “I think the U.S. would like to see other leaders in the region responding similarly to China’s aggressive actions.”