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U.S. sends warship within 12 nautical miles of one of China's artificial islands

Move viewed as potential challenge to China in South China Sea

Washington CNN  — 

The United States sent a warship very close to one of China’s artificial islands in the South China Sea on Tuesday, a potential challenge to Beijing’s territorial claims in the contested waters.

A U.S. defense official told CNN that the destroyer USS Lassen “conducted a transit” within 12 nautical miles of Subi Reef in the Spratly Islands on Tuesday morning local time.

The operation put the ship within an area that would be considered Chinese sovereign territory if the U.S. recognized the man-made islands as being Chinese territory, the official added.

The mission, which had the approval of President Barack Obama, has now concluded, the official said.

The United States had not breached the 12-mile limit since China began massive dredging operations to turn three reefs into artificial islands in 2014.

In little more than 18 months, China has reclaimed more than 2000 acres at three main locations in the Spratly Islands – Subi, Mischief and Fiery Cross reefs.

The South China Sea is the subject of numerous rival and often messy territorial claims, with China, Brunei, Malaysia, the Philippines, Taiwan and Vietnam disputing sovereignty of several island chains and nearby waters.

On Tuesday morning before it was confirmed that the U.S. warship had breached the 12-mile zone, Wang Yi, China’s foreign minister, said:

“We advise the U.S. side to think twice before action, not to conduct any rash action, and not to create trouble out of nothing.”

China has repeatedly said its activity in the South China Sea does not target any other country or affect freedom of navigation by sea or air.

In May, a U.S. surveillance plane carrying a CNN crew swooped over the Spratly Islands, triggering eight warnings from the Chinese navy to back off.

‘Routine operation’

Another defense official told CNN that the operation was “routine” and was in accordance with international law.

“We will fly, sail and operate anywhere in the world that international law allows,” the official said.

“U.S. Freedom of Navigation operations are global in scope and executed against a wide range of excessive maritime claims, irrespective of the coastal state advancing the excessive claim,” the official added.

His comments echoed those of State Department spokesman John Kirby on Monday, who said one country didn’t need to consult another “when you are exercising the right of freedom of navigation in international waters.”

Zhu Haiquan, the spokesperson of the Chinese Embassy in Washington said: “Freedom of navigation and overflight should not be used as excuse to flex muscle and undermine other countries’ sovereignty and security.”

“We urge the United States to refrain from saying or doing anything provocative and act responsibly in maintaining regional peace and stability,” Zhu said in a statement Monday night.

The rest of the region, wary of China’s intentions in the disputed waters, are likely to welcome the U.S. move.

Japan’s Chief Cabinet Secretary Yoshihide Suga decl