The United States must stop flexing its military muscle in waters near China's Nansha Islands in the South China Sea, Foreign Minister Wang Yi told US Secretary of State John Kerry in a recent phone call.

Wang made the remarks on Sunday, a day after China's Ministry of National Defense said the US had committed a "serious military provocation" by flying two Air Force B-52 bombers over a Chinese island in the South China Sea on Dec 10. The US said one plane had strayed off course.

A US destroyer, the USS Lassen, sailed within 12 nautical miles (22.2 kilometers) of China's Zhubi Reef on Oct 27.

Analysts said the intrusions by US vessels and aircraft into waters and airspace near the Chinese islands might prompt China to increase defensive measures in the area.

Wang, in Cyprus on an official trip, also urged the US to respect China's core interests and major concerns.

"The world is facing a whole range of global challenges and it calls on efforts by all parties. While seeking cooperation from China, the US should respect China's core interest and major concerns," Wang was quoted as saying in a foreign ministry statement.

The statement quoted Kerry as saying that the US is willing to deal with China's concerns seriously and will exchange views with Beijing over issues that may affect bilateral cooperation.

In his phone call, Wang also called for the US to stop selling arms to Taiwan.

China lodged a strong protest and summoned the top US diplomat in Beijing last week following the US Congress' approval of the latest round of $1.83 billion in arms sales to Taiwan. The arms sales have for decades been a major stumbling block for a smooth bilateral relationship between Beijing and Washington.

Chinese Vice-Foreign Minister Zheng Zeguang said in a statement last week that China has decided to take necessary measures, including imposing sanctions against the US companies involved in the arms sales.

US State Department spokesman John Kirby confirmed the phone conversation between the two on Sunday. He said they discussed a range of global and bilateral issues, such as the implementation of the JCPOA (Joint Comprehensive Plan to Action) to ensure Iran's nuclear program to be exclusively peaceful, the agreement reached on Syria last Friday at the United Nations, and the step forward down the political process.

Kirby mentioned that the two also discussed security in the South China Sea, but he declined to reveal any details of the conversation, especially regarding the B-52 incident.

While saying that the US continues to sail, fly and operate its military assets where it needs, according to international law, he said he was not referring to that particular B-52 flight, and the Pentagon has already talked about it.

"I was not talking about this flight but more broadly," Kirby said at the daily news briefing on Monday.

Zhang Junshe, a researcher at the PLA Naval Military Studies Research Institute, said the repeated provocations by the US "have endangered personnel and facilities on the islands". If the US continues with such actions, China will be forced to increase defensive measures in this area, including aircraft and sea patrols, he said.

Da Wei, a researcher at the China Institutes of Contemporary International Relations, said it was not the first time that a US military vessel or aircraft had entered waters or airspace near the Chinese islands.

"The US owes China a clear explanation about the latest incident," he said.

Contact the writers at chenweihua@chinadaily.com.cn