US destroyers sail in disputed South China Sea amid trade tensions

Shortly after that operation, China accused the United States of trespassing in its territorial waters - and said it had deployed missiles "capable of targeting medium and large ships".

Speaking about the most recent operation, Commander Clay Doss, a spokesman for the U.S. Navy's 7th Fleet, told CNN that the action was meant to "to challenge excessive maritime claims and preserve access to the waterways as governed by global law".

The US Navy sent two guided-missile destroyers to challenge China in the South China Sea, and Beijing is outraged. Clay Doss, a spokesman for the US Navy's 7th Fleet, told CNN.

Beijing sharply criticised the operation.

China claims most of the energy-rich South China Sea, as do several of its neighbors, including the Philippines, Vietnam, and Taiwan.

Chinese Foreign Ministry spokeswoman Hua Chunying also struck an upbeat tone about the talks, telling a news briefing: "We, of course, hope, and the people of the world want to see, a good result". Beijing rejected the ruling and the authority of the tribunal.

The Chinese military has since bolstered its presence in the region through deploying surface-to-air missiles, anti-ship missiles, jamming technology, and other defence systems to Chinese-occupied territories.

Speaking at a meeting of the Atlantic Council in Washington last week, Admiral John Richardson, chief of US Naval Operation, called for firmer rules governing naval encounters in disputed waters such as the South China Sea.

An unnamed USA official told Reuters on Monday that the two destroyers conducted a freedom of navigation exercise - the second by the U.S. in the region this year - within 12 nautical miles of Mischief Reef, where Beijing has purportedly built military facilities.

China then accused the U.S. of trespassing, and Chinese media announced it had deployed a "far-reaching anti-ship ballistic missile", the DF-26, that was "capable of targeting medium and large ships".

Tensions have been high for years between Washington and Beijing in the South China Sea, with the USA regularly drawing Chinese ire.

Preliminary discussions had been expected to start on Monday, according to the White House, before US Trade Representative Robert Lighthizer and Treasury Secretary Steven Mnuchin step in for the main event on Thursday and Friday.

"The relevant actions of the USA warships violated Chinese sovereignty, and undermined peace, security, and order in the relevant sea areas", Hua said.

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