The governing DPP, which champions Taiwan’s separate identity, will be seeking a third term in elections on Saturday.

Hundreds of thousands of people attended final pre-election rallies in Taiwan on Friday in advance of critical presidential and parliamentary polls on Saturday.

“The Chinese People’s Liberation Army maintains high vigilance at all times and will take all necessary measures to firmly crush ‘Taiwan independence’ attempts of all forms,” China’s defence ministry spokesperson Zhang Xiaogang said in a statement.

Responding to a question on Taiwan’s air force upgrading F-16 fighter jets and buying more from the United States, Xiaogang said even with purchases of US weapons the governing Democratic Progressive Party (DPP) “cannot stop the trend of complete reunification of the motherland”.

Taiwan has been a democratic success story since holding its first direct presidential election in 1996, the culmination of decades of struggle against authoritarian rule and martial law.

The DPP, which champions Taiwan’s separate identity and rejects China’s territorial claims, will be seeking a third term in office with its candidate, current Vice President Lai Ching-te.

China has framed the elections as a choice between “peace and war”, calling the DPP dangerous separatists and urging Taiwanese to make the “right choice”.

The DPP has rejected China’s sovereignty claims, and said only Taiwan’s people can decide their future. Speaking at a rally in Taipei’s neighbouring city New Taipei, Lai said the world was watching how Taiwan voted.

“If Taiwan moves closer to China again, Taiwan will lose its advantage, and foreign investment in Taiwan is more likely to be suspended or stopped,” he told the crowd. “Therefore, Taiwan must win this battle.”

China repeatedly denounced Lai in the run-up to Saturday’s election and rebuffed repeated calls from him for talks.

Al Jazeera’s Tony Cheng, reporting from Taipei, said Taiwan had witnessed Chinese military actions “in the background” over the past few weeks. “There have been military exercises, information gathering balloons flying overhead, and we’ve even seen in the last week a Chinese satellite causing an alert across the island,” Cheng said.

Lai is facing two opponents for the presidency – Hou Yu-ih of Taiwan’s largest opposition party the Kuomintang (KMT) and former Taipei mayor Ko Wen-je of the small Taiwan People’s Party (TPP), only founded in 2019.

Hou wants to re-start engagement with China, beginning with people-to-people exchanges, and has, like China, accused Lai of supporting Taiwan’s formal independence. Lai has said Hou is pro-Beijing, which Hou rejected.

“If Lai Ching-te is elected, the Taiwan Strait will likely fall into turmoil. Do you also want Taiwan to fall into war, folks?” Hou told his supporters.

Ko has won a passionate support base, especially among young voters, for focusing on bread-and-butter issues like the high cost of housing. He also wants to re-engage China, but insists that cannot come at the expense of protecting Taiwan’s democracy and way of life.

Al Jazeera’s Cheng said, “All three parties can see that China is a threat and their platforms are pretty much the same when it comes to China, so this [election] may go down to domestic issues.”

Polls open at 8am local time (00:00 GMT) and close at 4pm (08:00 GMT), with ballot counting by hand starting almost at once.

The result should be clear by late evening Saturday when the losers concede and the winner gives a victory speech.