Last week, a Chinese military plane approached within six meters of the nose of a US air force aircraft in the contentious South China Sea, forcing it to do evasive maneuvers in international airspace to avoid a collision.

According to the United States, the close encounter followed a recent trend of increasingly risky behavior by Chinese military aircraft.

The incident, involving a Chinese Navy J-11 fighter jet and a US air force RC-135 aircraft, occurred on December 21, according to a statement from the US military.

"We expect all Indo-Pacific nations to use international airspace securely and in conformity with international law," the statement continued.

The embassy of China in Washington, DC, did not reply quickly to a request for comment.

China has previously stated that the United States deployment of ships and aircraft in the South China Sea is not conducive to peace.

US military aircraft and vessels often conduct surveillance missions and transit the region.

China lays claim to broad portions of the South China Sea that overlap with the exclusive economic zones of Vietnam, Malaysia, Brunei, Indonesia, and the Philippines.

Each year, trade worth trillions of dollars passes through the river, which also features abundant fishing grounds and gas resources.

In a November meeting with his Chinese colleague, US Defense Secretary Lloyd Austin brought up the need to strengthen crisis communications and underlined what he termed the risky behavior of Chinese military aircraft.

Despite tensions between the United States and China, US military officials have long worked to keep open lines of contact with their Chinese counterparts to lessen the risk of flare-ups and deal with any incidents.

In May, a Chinese fighter aircraft intercepted an Australian military surveillance plane in the South China Sea, according to the Australian defense department.

Australia stated that the Chinese jet came near the RAAF aircraft and ejected a "chaff bundle" containing small fragments of aluminum consumed by the Australian aircraft's engine.

In June, the Canadian military alleged that Chinese warplanes harassed its patrol aircraft while they watched North Korean sanction evasions, occasionally forcing Canadian jets to deviate from their flight patterns.

Relations between China and the United States have been complex, with friction between the world's two largest economies over Taiwan, China's human rights record, and China's military action in the South China Sea.

The August trip to Taiwan by US House Speaker Nancy Pelosi enraged China, which saw it as an attempt to intervene in its domestic affairs. China then conducted military exercises around the island.

The United States has no formal diplomatic relations with Taiwan but is required by law to supply the island with defensive capabilities.