The US, under the first "freedom of navigation" operation, has sent a navy warship near an artificial island in the disputed South China Sea. Chinese government promptly reacted to the development calling the move "provocative action" violating its territorial sovereignty.
The guided-missile destroyer, USS Dewey, conducted a patrol within 20 km of Mischeef reef, part of the Spratly Islands over which several countries, including China, have competing claims.
This is the first of its kind exercise after October. What is intriguing is that the move come close on the heels of friendly exchanges between the US and China to settle trade issues and to cooperate in curbing the nuclear programme of North Korea, a Chinese ally.
Pentagon spokesman Jeff Davis said, "We operate in the Asia-Pacific region on a daily basis, including in the South China Sea. We operate in accordance with international law. It is not about any one country, or any one body of water," he said.

But China reacted saying the US warship had entered the South China Sea "without permission".
"The relevant action taken by the US vessel undermines China's sovereignty and security interests," foreign ministry spokesman Lu Kang told reporters in Beijing.
"We urge the US to correct this mistake," he said.
"Stop taking further provocative actions that hurt China's sovereignty and maritime interests, so as to avoid hurting peace and security of the region and long-term cooperation between the two countries."