TAIPEI, Taiwan — With tensions soaring in the Taiwan Strait, China responded to Taiwanese overtures for dialogue by releasing new footage showing a large-scale military exercise simulating an invasion and a purported confession from a Taiwanese businessman held captive in China on spying charges.

The double-barreled release by the influential China Central Television late Saturday and Sunday signaled a hard line from Beijing on the same weekend that Taiwanese President Tsai Ing-wen offered conciliatory remarks expressing a desire to hold talks as fears grow that China's increasing threats toward Taiwan could spill over into military action.

Marking the Oct. 10, 1911, establishment of the Republic of China on Saturday, Tsai delivered a speech in the Taiwanese capital asking Beijing to change its bellicose posture and "jointly facilitate cross-strait reconciliation and peaceful dialogue" — wording that was viewed by both sides of the Taiwan Strait as extending an olive branch amid growing talk of war.

China quickly dismissed Tsai's outreach. Hours after her speech, CCTV released a two-minute 30-second video and report of a "multidimensional" drill off China's southeastern coast featuring amphibious landing craft, attack helicopters and land-based missiles. The segment was the most extensive in a recent string of Chinese propaganda videos, featuring stirring music and quick cuts, warning that the military could attack if Tsai's Democratic Progressive Party (DPP) did not recognize a diplomatic formulation that regards China and Taiwan as part of a single country or if Taipei deepened its relationship with its military and diplomatic backer, the United States.

Beijing's Taiwan Affairs Office spokesman Zhu Fenglian said Saturday that Tsai, not Beijing, was the instigator. The "root cause for cross-strait tensions is the DPP leadership that refuses to recognize . . . the one-China principle" and "colludes with external forces," Zhu said.

China considers Taiwan a breakaway province that must be "reunified" with it to restore the territory controlled by the Chinese empire at its 19th-century apex. But the Communist Party never ruled Taiwan despite taking power in China in 1949 following a civil war, and citizens in democratic Taiwan have increasingly voted in recent years against a closer union with Beijing.

Chinese President Xi Jinping has made bringing Taiwan under Beijing's control a core plank of his vision to restore China's greatness and has signaled growing impatience with the DPP's refusal to acknowledge the one-China principle. In its annual work report this year, the Chinese government removed the word "peaceful" from long-standing references to "reunification" with Taiwan.

Late on Sunday, CCTV made another pointed disclosure: It aired a supposed confession from detained Taiwanese businessman Lee Meng-chu, who was shown for the first time since he disappeared last year in southern China. Lee was shown in prison garb apologizing for activities that endangered Chinese national security and supporting Hong Kong's and Taiwan's independence.

Lee's arrest, CCTV said, was part of a new Chinese counterintelligence campaign called "Thunder 2020" that would target Taiwanese citizens suspected of spying and fomenting unrest in Hong Kong.

Taiwan reacted angrily on Monday, saying it believed China forced Lee to "confess to crimes and express repentance on its official media, which completely does not fit with normal legal procedure."

China has been repeatedly criticized by human rights groups and foreign governments, including the United States, Britain, Canada and Australia, for airing forced confessions from political prisoners and holding political hostages.

Lee was detained in August 2019 in China after he photographed Chinese armored vehicles amassing in Shenzhen, the mainland city bordering Hong Kong, and shared them on social media.

As protests against China's encroachment swelled in Hong Kong last summer, Chinese state media widely publicized troop activities along the border to signal that it could intervene dramatically in the ostensibly semiautonomous city if violent protests spiraled.

CCTV said Sunday that Lee traveled to Shenzhen for the sole purpose of filming the military equipment and took 16 videos and 48 photos.

Taiwanese officials in recent weeks have appeared to take steps to dial back tensions with China after hosting two high-ranking U.S. officials for visits and securing major weapons purchases from the Trump administration. Last month, Taiwanese Foreign Minister Joseph Wu told NPR that Taiwan did not seek to establish a formal diplomatic relationship with Washington, which would be a major boost for Taiwan's international diplomacy but also highly provocative to Beijing.

Hu Xijin, editor of the Global Times, a hawkish Chinese Communist Party newspaper, said on Chinese social media that Tsai's administration had "softened" its tone because it "fathomed the severity of a possible military conflict" with China.

He urged China not to be "fooled" by the goodwill gesture. "Continued military muscle-flexing is the only answer to cross-strait stability," Hu said.