China Tests Military’s Combat Readiness After Joe Biden’s Taiwan Pledge

China‘s armed forces have held combat exercises in the seas and skies around Taiwan in response to “collusion” between Washington and Taipei, a military spokesperson said on Wednesday.

The People’s Liberation Army‘s Eastern Theater Command said it had conducted a “joint forces combat readiness patrol” in recent days, but didn’t give a precise timeline for the pointed training drills. On Monday, Taiwan said it scrambled fighter aircraft to intercept at least 30 Chinese warplanes entering its air defense zone.

The statement comes one week after President Joe Biden told a press conference in Tokyo that the United States would intervene militarily if China were to invade Taiwan, an island the Chinese Communist Party has never governed, but which it claims is part of its territory. The Chinese military’s announcement also coincides with the visit to Taipei by Illinois Sen. Tammy Duckworth.

The combat drills were “a necessary action against U.S.-Taiwan collusion,” the command statement said. “Recently, the United States has frequently made moves on the Taiwan issue, saying one thing while doing another, overtly and covertly encouraging and supporting Taiwan independence forces. [The U.S.] will push Taiwan into a dangerous situation and also face serious consequences itself.”

President Tsai Ing-wen of Taiwan says the island democracy is already a functionally independent country. Her government has tracked an escalating number of Chinese military aircraft flights around the island over the past two years. Taiwan says it doesn’t seek conflict, but will fight to defend its freedoms.

In a widely anticipated China policy speech last week, Secretary of State Antony Blinken repeated the official position that the U.S. does not support Taiwan independence. To maintain peace and stability across the Taiwan Strait, the U.S. would continue to assist Taipei in maintaining its self-defense capacity, in accordance with the Taiwan Relations Act (TRA), he said.

“And, as indicated in the TRA, to maintain our capacity to resist any resort to force or other forms of coercion that would jeopardize the security or the social or economic system of Taiwan,” the secretary said.

Biden’s pledge to defend Taiwan was a rare pronouncement from the U.S. executive branch, whose otherwise careful messaging is also governed by State Department guidelines. When it comes to the legislative branch, however, frequent and unambiguous statements in support of Taiwan’s defense leave little doubt about where Congress stands on the subject.

Roughly six hours after more than two dozen Chinese warplanes buzzed Taiwan’s air space, Illinois’ Sen. Duckworth landed in Taipei for a surprise three-day visit. The combat veteran was last in Taiwan a year ago this month.

In a televised meeting with Taiwan’s president, the senator emphasized broad U.S. support for the island’s security and the U.S.-Taiwan economic partnership.

Duckworth noted “tremendous support for Taiwan” within Congress. “Our president has shown his support for Taiwan. You’ve heard from our military, and as a member of the legislative branch, I will tell you it is a bipartisan agreement that the U.S. should stand with Taiwan,” she said.

China generally opposes all interactions between the U.S. and Taiwan. The Chinese Embassy in Washington and the Foreign Ministry in Beijing said they “lodged solemn representations” with their American counterparts.

“Taiwan is a province of China. What president does it have to speak of?” Zhao Lijian, a Foreign Ministry spokesperson, told reporters at a regular media briefing on Tuesday.

Duckworth’s office didn’t response to a request for comment.