The U.S. military said Thursday that its patrol aircraft had a close call with a Chinese fighter jet in international airspace over the South China Sea last week.

According to the U.S. Indo-Pacific Command, a J-11 fighter of the Chinese navy flew within some 6 meters of the nose of an RC-135 reconnaissance plane of the U.S. Air Force on Dec. 21.

The "unsafe" flight forced the U.S. plane to take evasive maneuvers to avoid a collision, the command said in a statement.

"We expect all countries in the Indo-Pacific region to use international airspace safely and in accordance with international law," the statement said, noting the U.S. airplane was conducting routine operations at the time.

The U.S. military posted a video, purportedly taken from the U.S. airplane, on its website that showed an aircraft believed to be a J-11 fighter flying close by for an extended period before leaving.

China reacted sharply to the U.S. claim, with Foreign Ministry spokesman Wang Wenbin saying at a press conference Friday in Beijing that Washington's "provocative and dangerous actions" are the root cause of maritime security issues and that the United States should stop them.

Wang said the United States has "seriously endangered China's national security" by frequently sending ships and planes to conduct reconnaissance at close range. Beijing calls on Washington to stop making false accusations and smearing China, he added.

U.S. Defense Secretary Lloyd Austin expressed concerns to his Chinese counterpart Wei Fenghe about "the increasingly dangerous behavior" demonstrated by Chinese military aircraft in the Indo-Pacific area, during their meeting in Cambodia last month.

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