TAIPEI, 26 Feb (REUTERS) -- A US warship sailed through the sensitive Taiwan Strait on Saturday (Feb 26), part of what the US military calls routine activity, which nonetheless irritates China.

The US Navy's 7th Fleet said the Arleigh Burke-class guided-missile destroyer USS Ralph Johnson was conducting a "routine" transit through international waters.

"The ship's transit through the Taiwan Strait demonstrates the United States' commitment to a free and open Indo-Pacific," 7th Fleet spokesperson Nicholas Lingo said in a statement. "The United States military flies, sails, and operates anywhere international law allows."

China's Defence Ministry did not immediately respond to a faxed request for comment.

Taiwan's Defence Ministry said the ship sailed in a northerly direction through the strait, and that its forces had monitored its passage and observed nothing out of the ordinary.

Taiwan is currently in a heightened state of alert due to Russia's invasion of Ukraine, nervous that China may try to take advantage of the situation to make a move on the island though the government has reported no unusual Chinese manoeuvres.