Washington DC - The US has approved a $619-million potential sale of weapons to Taiwan to help boost the island's defense capability, angering China in the process.

Taiwan's foreign ministry said on Thursday that the deal is the Biden administration's ninth arms sale to Taiwan, which fulfills its promise to normalize a policy to sell military equipment and services to Taiwan.

The US is legally bound to support Taiwan's defense capabilities due to the 1979 Taiwan Relations Act.

The US Defense Security Cooperation Agency (DSCA) said in a Wednesday statement that the deal includes missiles and equipment to be used with F-16s fighter jets, including anti-radiation missiles, air-to-air missiles and launchers.

China China responds to Russia's threat to use nuclear weapons in Ukraine

"The proposed sale will contribute to the recipient’s capability to provide for the defense of its airspace, regional security, and interoperability with the United States," US DSCA said.

It said the deal would help improve Taipei's security and assist in maintaining political stability, military balance and progress in the region.

In Taipei, Taiwan's Ministry of National Defense expressed gratitude for the approval, adding that the deal is expected to take effect one month after US Congress is notified.

The ministry said the deal would further help Taiwan's Air Force strengthen its capability to defend the island's airspace in face of Chinese air force incursions.

The deal drew ire from China, as it considers self-ruled Taiwan part of its territory, despite the island having an independent government since 1949.

China Dozens of Hong Kong democracy campaigners sentenced in crackdown that sparks outrage

The Chinese leadership expressed their opposition on Thursday. The arms deliveries "undermine China-US relations and peace and stability in the Taiwan Strait," said Foreign Ministry spokesperson Mao Ning in Beijing. China called on the US to stop arms sales and military contacts with Taiwan.

Meanwhile, Taiwan's Defense Ministry on Thursday reported a second day of large-scale Chinese air force incursions. Over the prior 48 hours, at least 40 Chinese fighter jets were detected in Taiwan's airspace, it said.