U.S. Defense Secretary Chuck Hagel has accused China of being a “destabilizing” force in the South China Sea, prompting a rebuke from Beijing in which Washington was accused of “threat and intimidation.”

The diplomatic contretemps occurred at an international security conference Saturday in Singapore, during which Hagel confronted China’s handling of territorial disputes with its Asian neighbors in forthright language.

"In recent months, China has undertaken destabilizing, unilateral actions asserting its claims in the South China Sea,” he said, adding that the U.S. "will not look the other way" when international maritime rules and standards were being ignored.

The comments led to an immediate response from Beijing. Lt. Gen. Wang Guanzhong, deputy chief of the General Staff, told Hagel: "you were very candid this morning and, to be frank, more than our expectation."

In comments to reporters, he later added: "I felt that Secretary Hagel's speech is full of hegemonism, threat and intimidation."

Reporters were taken from the meeting room before Hagel responded. But Pentagon press secretary Rear Adm. John Kirby said Hagel told Wang that all regional disputes should be solved through diplomacy, and Hagel encouraged China to foster dialogue with neighboring nations.

Hagel also used his speech at Singapore's Shangri-La Dialogue, Asia biggest security forum, to single out China for cyberspying against the U.S. While this has been a persistent complaint by the U.S., it was less than two weeks after the Obama administration charged five Chinese military officers with hacking into American companies to steal trade secrets.

The Chinese, in response, suspended participation in a U.S.-China Cyber Working Group, and released a report that said the U.S. is conducting unscrupulous cyberespionage and that China is a major target.

Noting the suspension, Hagel said the U.S. would continue to raise cyberissues with the Chinese "because dialogue is essential for reducing the risk of miscalculation and escalation in cyberspace."

But it is his comments on the ongoing dispute in the South China Seas that is likely to draw most attention.

In comments aimed directly at China, Hagel said the U.S. opposes any country's use of intimidation or threat of force to assert territorial claims.

"All nations of the region, including China, have a choice: to unite, and recommit to a stable regional order, or, to walk away from that commitment and risk the peace and security that has benefited millions of people throughout the Asia-Pacific, and billions of people around the world," he said.