Saturday’s drill will coincide with a rally in Taiwan’s Kaohsiung city at which the ruling Democratic Progressive Party will try to mobilize 1 million people to demonstrate support for the island’s frustrated bid for membership of the United Nations. Many security analysts see the Taiwan Strait, the 180-km (110-mile) stretch of water between China and its tiny neighbor, as one of the most dangerous flashpoints in Asia.

Chinese academics have said China would be forced to react, possibly militarily, if the referendum was passed, even though the U.N. bid is doomed due to an absence of diplomatic support.

“This is an undisguised Taiwan independence splittist act. It’s provocation,” Li Weiyi, spokesman for the Taiwan Affairs Office, told a news conference on Wednesday.

“If Chen Shui-bian insists on having it his way, he will have to accept all grave consequences arising from this,” he said.