China’s local maritime authorities have issued a warning for possible rocket debris in waters northeast of Taiwan, saying ships would be banned from entering the area on April 16.

Southern Fujian province's Maritime Safety Administration said that vessels would be prohibited from entering the waters from 9:00 a.m. to 3:00 p.m. on that day, according to a press release on Thursday.

The announcement comes after China held large-scale military drills that formally ended Monday in response to Taiwanese President Tsai Ing-wen's transit visit last week to the United States, where she met U.S. House Speaker Kevin McCarthy in California. Tensions remain high and China sent warplanes flying toward Taiwan more than 200 times over the weekend, while its navy ships circled the self-ruled island.

CHINA CONDUCTS SECOND DAY OF MILITARY DRILLS AROUND TAIWAN, SIMULATES STRIKES ON THE ISLAND

The announcement designates a rectangular area northeast of Taiwan in the East China Sea.

The notice sheds more light on the no-fly zone that China had warned it was setting up earlier this week. Taiwan’s Ministry of Transportation said Wednesday it had received a notice from China’s Civil Aviation Administration that it would establish a control zone to "restrict flights" in parts of northern Taiwan from April 16-18, in effect setting up an area where flights would not be allowed to go.

Taiwan said it strongly protested the notice and was able to get China to reduce the flight ban time from three days to 27 minutes on the morning of April 16. It is unclear what China plans to do at that time. Taiwan’s Defense Ministry said Wednesday it was looking into the matter but could not provide further details.

China claims Taiwan as part of its own territory, and the claim is a point of contention in Beijing's relationship with the U.S., which is the island’s biggest unofficial ally. The U.S. sells Taiwan weapons and a slew of U.S. lawmakers have visited the island in the past year in a demonstration of support.