China is conducting “large-scale” military drills near the island nation of Taiwan. These drills are coming just days after China sanctioned some United States defense firms over its delivery of weapons to Taiwan.

China sees Taiwan’s push to ramp up its defence this year as an act of defiance. It has enraged Beijing, which claims the self-ruled island as its own territory. “Any sinister schemes to obstruct China’s reunification are doomed to fail,” the ministry’s spokesman Lin Jian said at a regular press briefing on Monday.

In a post on Weibo, as reported by the BBC, the Chinese military’s Eastern Theater Command, which is in charge of the Taiwan Strait, described the upcoming military exercise as a “shield of justice.”

“All those plotting independence will be annihilated upon encountering the shield!” the post read.

China Sanctions U.S. Defense Firms

According to a report by ZeroHedge, the multi-day live-fire exercises and simulated strikes are intended to prepare China for a blockade of Taiwan’s main ports. The drills come one week after the U.S. announced an $11.1 billion arms sale to Taiwan, the largest-ever U.S. weapons package to the island. The package includes HIMARS rocket systems, howitzers, Javelin anti-tank missiles, Altius loitering munition drones, and other weapon systems.

This also comes not long after China released footage of a “carrier-killer” hypersonic missile being launched from a destroyer. A hypersonic missile is one that is launched at a speed greater than Mach 5, which will cause significant differences in behavior due to chemical reactions or dissociation of the air.

China Unveils New Footage Of Carrier-Killer Hypersonic Missile Launch From Destroyer

“[Chinese rulers] are sending a strong message on external interference,” Chieh Chung, a researcher at Taiwan’s Institute for National Defense and Security Research, told Reuters. He noted that China had “completely cut off” air and sea routes with Japan across three zones north of Taiwan.

Taiwan’s ruler said that these drills underscore the need to continue strengthening defense capabilities amid Beijing’s continued pressure on what it considers a breakaway province.