China announced on Monday that it is expanding its military drills around Taiwan, which have interrupted shipping and air traffic and significantly heightened worries about the prospect for confrontation in a critical region for global trade.

Joint anti-submarine and sea assault operations drills have been announced by China's Eastern Theater Command in response to concerns that Beijing is stepping up its pressure on Taiwan's military capabilities.

According to social media posts from the eastern leadership of China's ruling Communist Party's military branch, the People's Liberation Army, the exercises would include anti-submarine maneuvers that appear to target U.S. support for Taiwan in the case of a possible Chinese invasion.

The Taiwanese Ministry of Foreign Affairs decried the action, stating that China, which claims Taiwan as its own territory, was purposely provoking tensions. It requested that Beijing cease its military actions and "retreat from the brink."

"In the face of China's military intimidation, Taiwan will not be frightened and will defend its sovereignty, national security, and free and democratic way of life with greater vigor," the ministry said in a statement.

In his first public comments on the matter since Pelosi's visit, U.S. President Joe Biden stated that he was not worried about Taiwan but was concerned about China's actions in the region. 

Biden told reporters in Delaware, "I'm worried with how frequently they're moving... however, I don't believe they'll do anything beyond what they're already doing." 

"We have condemned them since they began to escalate... They are provocative and irresponsible, and they increase the possibility of miscalculation. And it was to this that the president was referring," the spokesperson for the White House, Karine Jean-Pierre, stated. 

China reacted to Pelosi's visit by launching ballistic missiles over Taiwan for the first time, and by abandoning some lines of cooperation with the United States, including theater military negotiations and discussions on climate change.  

The chief of U.S. drug control strategy, Rahul Gupta, deemed Beijing's decision "unacceptable" on Monday, citing the suspension of channels relating to illicit fentanyl trafficking. 

Uncertainty surrounds the duration and the location of the most recent drills, but Taiwan has already loosened flight restrictions within the six previous Chinese training zones surrounding the island. 

The Singaporean prime minister, Lee Hsien Loong, issued a warning about the possibility for miscalculation about the Taiwan Strait tensions.