The Taiwan Strait does not belong to China and any attempts to create tension threaten global security, the island's defense ministry said on Monday, after Beijing criticized Canada for sailing a warship through the sensitive waterway.
The US Navy and occasionally ships from allied countries like Canada, Britain and France transit the strait, which they consider an international waterway, around once a month.
Taiwan also considers it an international waterway but China, which claims Taiwan as its own territory, says the strategic waterway belongs to it.
Last week the first US Navy ships transited the strait since President Donald Trump took office last month, drawing an angry reaction from China, which said the mission increased security risks.
Taiwan's defense ministry said China had responded to those sailings by carrying out "joint combat readiness patrols."
"The Taiwan Strait is absolutely not within the scope of China's sovereignty," the ministry said in a statement.
Freedom of navigation by "friendly and allied" countries through the strait are concrete actions that highlight the strait's legal status, and China is trying to create a false appearance that the strait is an "internal issue," it added.
"Peace and stability in the Taiwan Strait is not only a matter of concern for Taiwan, but also a common concern for free and democratic countries around the world," the ministry said.
"Any deliberate attempts by the communist's military to create tension in the Taiwan Strait will pose a real threat to global security," the ministry said.
Neither China's defense ministry nor the Taiwan Affairs Office responded to requests for comment.
Taiwan has complained of repeated Chinese military activities near the island.
Its defense ministry said on Monday morning in its daily update of China's actions over the previous 24 hours that it had detected 41 Chinese military aircraft and nine ships around the island, concentrated in the strait and off Taiwan's southwest.
China's military lambasted Canada on Monday for sailing the warship through the strait.
Canada's actions "deliberately stirred up trouble" and undermined peace and stability in the strait, the People's Liberation Army's Eastern Theater Command said in a statement.
"Theater forces maintain a high level of alert at all times and resolutely counter all threats and provocations," it added.
Canada's Department of National Defense said in a statement that the Royal Canadian navy ship HMCS Ottawa recently conducted a transit throughout the Taiwan Strait.
"Canada has undertaken a number of transits through the Taiwan Strait to uphold the important principle of operating freely through international waterways in accordance with international law,” the department said.
Taiwan's defense ministry said on Sunday that the ship had sailed in a northerly direction, adding that Taiwanese forces also kept watch.
Taiwan's foreign ministry welcomed the sailing.
"Canada has once again taken concrete actions to defend the freedom, peace and openness of the Taiwan Strait and has demonstrated its firm position that the Taiwan Strait is international waters," it said on Sunday.
In October, a US and a Canadian warship sailed together through the strait, less than a week after China conducted a new round of war games around the island.
Taiwan's democratically elected government rejects Beijing's sovereignty claims, saying only that the island's people can decide their future.