The Trump administration took another step toward a far more confrontational stance against China by giving the green light for another so-called freedom of navigation operation (FONOP) in Chinese-claimed waters in the South China Sea on Sunday.

The US Navy sent the guided-missile destroyer USS Stethem within the 12-nautical-mile territorial limit around Triton Island in the Paracel island group, which has been under Chinese control since 1974. The latest operation comes less than six weeks after an incursion by the USS Dewey close to the Chinese-held islet of Mischief Reef in the Spratly island group.

Sunday’s naval provocation followed last week’s US approval of a substantial $1.4 billion arms deal to Taiwan and imposition of sanctions on Chinese companies and individuals over their involvement in trade with North Korea.

Chinese foreign ministry spokesman Lu Kang denounced the arms sale as impinging on the country’s sovereignty and “contrary to Washington’s commitment to the One China policy,” under which the US recognises Beijing as the sole legitimate government of all China, including Taiwan.

Beijing also expressed concerns last week over legislation approved by a US Senate panel to allow US warships to make regular port visits to Taiwan.

Responding to Sunday’s US naval intrusion, Lu called on Washington to “immediately stop such kinds of provocative operations that violate China’s sovereignty and threaten China’s security.” He warned: “The Chinese side will continue to take all necessary means to defend national sovereignty and security.”

Lu said China had sent military vessels and fighter aircraft to warn off the US destroyer, adding that “the Chinese side is dissatisfied with, and opposed to, the relevant behaviour of the US side.” He accused Washington of “deliberating stirring up troubles in the South China Sea” and running counter to the desire of other countries in the region for stability.

The despatch of Chinese fighters and naval ships underscores the recklessness of the Trump administration’s actions. They could lead to a military incident, either accidental or deliberate, that triggers a broader conflict between the two nuclear-armed powers.

The US has dismissed Chinese territorial claims in the South China Sea as excessive and repeatedly declared it has no intention of abiding by them. As well as carrying out more frequent intrusions close to Chinese islets, the US navy has boosted its presence and carried out more frequent exercises in the strategic sea.

The Pentagon regards the South China Sea as a vital component of its AirSea Battle strategy for war with China. The plan envisages massive air and missile attacks on the Chinese mainland from US warships, submarines and military bases in the region. Triton Island, the most southerly of the Paracel group, lies some 400 kilometres south of China’s Hainan Island, which houses key strategic naval bases.

Yesterday’s naval intrusion is another sign that Donald Trump’s administration is frustrated by China’s failure to force North Korea to abandon its nuclear and missile programs.

During last year’s US presidential election campaign, Trump repeatedly resorted to anti-China demagogy and vowed to take trade war measures against China, including branding it as a currency manipulator. Following his election win, Trump ramped up the threats over China’s activities in the South China Sea and even spoke of abrogating the One China policy, which has been the bedrock of US-Chinese relations for nearly four decades.

Trump wound back his rhetoric in April when he met with Chinese President Xi Jinping, who indicated that China would intensify its pressure on North Korea. Beijing has halted the import of North Korean coal and, in recent weeks, has reportedly wound back its export of oil to North Korea. China is by far North Korea’s largest trading partner and the source of most of its energy.

Trump officials, however, have warned on several occasions that the US was not prepared to wait indefinitely and its patience was running out. Late last month, Trump indicated that time had run out, declaring in a tweet that while he appreciated President Xi’s efforts, “it has not worked out.”

Trump underscored the message following talks with South Korean President Moon Jae-in Washington last Friday. Referring to the Obama administration’s policy of sanctions, Trump declared that the “era of strategic patience with the North Korean regime has failed. Frankly that patience is over.”

Trump has not spelled out what methods the US will turn to, but his officials have declared that the US will talk to Pyongyang only in the “right circumstances”—that is, if North Korea capitulates to US demands. The White House has insisted that “all options”—that is, including military attacks—are on the table. Three aircraft carrier strike groups, along with nuclear submarines, are currently stationed in the region of the Korean Peninsula.

The US “freedom of navigation” operation yesterday is a clear sign that the Trump administration intends to confront China, not only over North Korea, but across the board, including over Taiwan and trade matters. During Trump’s meeting with Moon, according to the New York Times, the president’s chief economic adviser Gary Cohn lashed out at China’s “many predatory practices in how they deal with us.”

Trump was due speak by phone yesterday evening (US time) with Chinese President Xi and Japanese Prime Minister Shinzo Abe ahead of scheduled meetings with both men at this week’s G20 summit in Germany. North Korea was at the top of the US agenda. As this article was due to be posted, the first reports of Trump’s phone conversation with Abe indicated that the two countries would step up their pressure on North Korea.