Mattis also struck at one of the key, longstanding disputes between the USA and China, telling the conference that America will continue to provide defense equipment and services to Taiwan and oppose any effort to alter the status quo.
In his speech at the Singapore summit, US Defence Secretary Jim Mattis said that Beijing's policy in the South China Sea "stands in stark contrast to the openness our strategy promotes".
His comments come just 24 hours after US Secretary of Defence James Mattis warned China of "consequences" if it continued to militarise the South China Sea.
"I believe there are much larger consequences in the future when nations lose the rapport of their neighbors. eventually these [actions] do not pay off", he said.
China has been accused of building artificial military islands in the disputed waterway in an apparent move to intimidate nations with rival claims to territory.
The comments came on the heels of a string of events that highlight the tension between the world's two biggest economies over the South China Sea's disputed waters.
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Claudio Tapia, president of the AFA, apologised for cancelling the match but said the safety of the players was at stake. She said the Argentinians had not objected to that and that Messi had wanted to visit holy sites in Jerusalem.
On Sunday, two US Navy warships sailed close to a handful of disputed islands claimed by China in the Paracel island chain, east of Vietnam, in a move that drew the ire of Beijing.
China's state-run Global Times newspaper said in an editorial that tension in the South China Sea was "due to the USA continuing to increase its military presence in the region, forcing China to naturally upgrade its defensive weapons on the islands".
Recent satellite photographs showed China appeared to have deployed truck-mounted surface-to-air missiles or anti ship cruise missiles at Woody Island.
In a dig at China, which the Pentagon has accused of using "predatory" economics to exploit neighbours, Mattis said the U.S. supports the peaceful resolution of disputes, "free, fair and reciprocal trade and investment" and adherence to worldwide rules and norms.
China's concept of common, comprehensive, cooperative and sustainable security has clarified the country's stance on issues of regional concern, contributing to long-term stability and development in Asia, Chinese delegates to the ongoing 17th Shangri-La Dialogue said Saturday.
He did however, seek to calm nervous allies in the region. "We see it as affirmation of the rules-based global order".
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The victor of the match will play either third seed Marin Cilic or Schwartzman's compatriot Juan Martin del Potro. Nadal hit a floater that was possibly headed wide, yet Schwartzman attempted a volley that missed.
"US support for Taiwan has always been strong [but] we will also have to see how the [US President Donald Trump] administration reacts ..." Washington had called on Beijing to remove these systems, AP reported.
The French Minister of Defense, Florence Parly, said she welcomes the signs of dialogue, but added that sanctions should continue until denuclearization is achieved in a full, verifiable and irreversible manner.
In an exchange with Mattis, Senior Colonel Zhao Xiaozhuo, deputy director of the Center on China-US Defense Relations in the PLA's Academy of Military Science, said that sending warships into Chinese territorial waters was a violation of the country's law.
The Pentagon is weighing a more assertive programme of so-called freedom-of-navigation operations close to Chinese installations on disputed reefs, according to United States officials.
Two U.S. warships sailed close to the Paracel Islands on May 27 in the latest freedom of navigation operation created to challenge Beijing's claims.
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And the lava keeps spewing, swallowing homes and igniting fears of more destruction to come. This latest disaster brings the total structures lost over the past month to well over 400.