A US Navy aircraft flew over the Taiwan Strait on Thursday to “demonstrate” Washington’s “commitment to a free and open” Indo-Pacific, a move slammed by China.

US military’s 7th Fleet, deployed for operations in the Asia-Pacific, said in a statement that the US Navy P-8A Poseidon transited the Taiwan Strait in “international airspace” on Thursday.

“By operating within the Taiwan Strait in accordance with international law, the United States upholds the navigational rights and freedoms of all nations,” the statement said.

China has often objected to the passage of US military planes and ships through the Taiwan Strait which divided the mainland from the island nation of Taiwan. Beijing considers Taiwan a "breakaway province."

"The troops of the PLA Eastern Theater Command have tracked and monitored the US aircraft in the whole course, and handled it in line with laws and regulations," said Senior Col. Shi Yi, spokesman for the Chinese PLA Eastern Theater Command.

However, the US Army’s 7th Fleet said: “The aircraft's transit of the Taiwan Strait demonstrates the United States' commitment to a free and open Indo-Pacific.”

Washington refers to its policy regarding the wider Asia-Pacific region as Indo-Pacific.

“The United States military flies, sails and operates anywhere international law allows,” said the 7th Fleet.

Shi stressed that the troops of the PLA Eastern Theater Command remain "on high alert at all times to resolutely safeguard China's sovereignty, security and regional peace and stability."

The US Navy aircraft’s voyage over Taiwan Strait comes as Taiwan detected 33 Chinese aircraft and nine vessels on Thursday.

Taiwan’s Defense Ministry said 24 of the detected aircraft crossed the median line of the Taiwan Strait or entered Taiwan’s southwest and southeast air defense identification zone (ADIZ).

Beijing neither recognizes the median line nor ADIZ.

The island nation, which has insisted on its independence since 1949, is set to hold Han Kuang annual military exercise from July 24 to 28.