China's foreign minister has dismissed reports that it has deployed an advanced surface-to-air missile system to one of the disputed islands it controls in the South China Sea.
"This is an attempt by certain Western media to create new stories," Wang Yi told reporters through an interpreter in Beijing on Wednesday (local time).
He said the media should instead focus on Chinese-built lighthouses on the islands ensuring naval safety.
Earlier Taiwan defence ministry spokesman Major General David Lo told Reuters the missile batteries had been set up on Woody Island. The island is part of the Paracels chain, under Chinese control for more than 40 years but also claimed by Taiwan and Vietnam.
"Interested parties should work together to maintain peace and stability in the South China Sea region and refrain from taking any unilateral measures that would increase tensions," Lo said on Wednesday.
A US defence official also confirmed the "apparent deployment" of the missiles, first reported by Fox News.
Images from civilian satellite company ImageSat International show two batteries of eight surface-to-air missile launchers as well as a radar system, according to Fox News.
News of the missile deployment came as Obama and leaders of the Association of Southeast Asian Nations concluded a summit in California, where they discussed the need to ease tensions in the region but did not include specific mention of China's assertive pursuit of its claims in the South China Sea.
China claims most of the South China Sea, through which more than $US5 trillion ($A7 trillion) in global trade passes every year, and has been building runways and other infrastructure on artificial islands to bolster its claims.
"We discussed the need for tangible steps in the South China Sea to lower tensions including a halt to further reclamation, new construction and militarisation of disputed areas," Obama told a news conference.
The US has said it will continue conducting "freedom of navigation patrols" by ships and aircraft to assure unimpeded passage through the region, where Vietnam, Malaysia, Brunei, the Philippines and Taiwan have rival claims.