Beijing says it has right to develop South China Sea islands

China on Tuesday said it has the right to develop islands in the South China Sea, responding to criticism from the U.S. on Sunday that Beijing had fully militarized three islands in the region.

Speaking to reporters on Tuesday, Foreign Ministry spokesperson Wang Wenbin called the islands "necessary national defense facilities" within Chinese territory in line with international law, according to The Associated Press.

Wang then criticized the U.S. of aiming to "stir up trouble and make provocations," which "seriously threatens the sovereignty and security of coastal countries and undermines the order and navigation safety in the South China Sea."

On Sunday, Adm. John C. Aquilino, the head of U.S. Indo-Pacific Command, said China had fully armed three small islands with anti-ship and anti-aircraft missile systems, lasers, jamming equipment and fighter jets.

Aquilino said Beijing was flexing its military muscles but also contradicted past assurances from Chinese President Xi Jinping, who promised not to militarize the artificial islands.

"I think over the past 20 years we've witnessed the largest military buildup since World War II by the PRC," Aquilino told the AP. "They have advanced all their capabilities and that buildup of weaponization is destabilizing to the region."

The contested nature of the waters was highlighted during the AP's trip aboard a P-8A Poseidon plane flying over the islands, when the pilots ignored radio messages warning it to stay away from the islands.

China has aggressively sought to expand its control of the South China Sea, amid competing claims from other countries including Vietnam and Taiwan. The U.S. has no claims but patrols the area in an effort to promote freedom of navigation.

Vice President Harris last year rebuked Beijing for intimidating other countries in the South China Sea.

"Beijing's actions continue to undermine the rules-based order and threaten the sovereignty of nations," she said at the time. "The United States stands with our allies and partners in the face of these threats."