China has denounced the patrol for threatening its sovereignty and security in the South China Sea.
"China always respects the freedom of navigation and overflight all countries enjoy under international law. But we are consistently opposed to relevant countries threatening and damaging the sovereignty and security of littoral countries under the flag of freedom of navigation and overflight," Chinese foreign ministry spokesman Geng Shuang told journalists commenting on the matter.
On Wednesday, Reuters, citing two unnamed US officials, reported that "China has nearly finished building almost two dozen structures on artificial islands in the South China Sea that appear designed to house long-range surface-to-air missiles."
"It is not like the Chinese to build anything in the South China Sea just to build it, and these structures resemble others that house SAM [surface-to-air missiles] batteries, so the logical conclusion is that's what they are for," the agency quotes a US intelligence official as saying.
Another official said the structures appeared to be 20 meters (66 feet) long and 10 meters (33 feet) high.
"China carrying out normal construction activities on its own territory, including deploying necessary and appropriate territorial defense facilities, is a normal right under international law for sovereign nations," he told reporters.
Meanwhile, Foreign ministers of the Association of Southeast Asian Nations (ASEAN) who were meeting on the Philippine Island of Boracay on Tuesday, noted the importance of sustaining the momentum of dialogue in easing the tensions in the disputed South China Sea.
They expressed concern over the possible militarization of some areas in the region.
Commenting on the developments in the region, Konstantin Sivkov, the president of the Moscow-based Academy of Geopolitical Problems noted that the coincidence in time of the US patrol in the South China Sea with the ministerial meeting of ASEAN and of the reports of China's buildings might mean a simultaneous US' pressure both on China and ASEAN.
"The US is mounting military tensions in the South China Sea," he told Sputnik.
The expert noted that even though the risk of a large-scale conflict remains highly unlikely, there could be a local military face-off between the fleets of the US and Japan on the one hand, and China on the other.
The expert further noted that there is a US geopolitical game going on in the region. The reports of China's constructions on the islands are the means of this game played against Beijing. However Washington knows only too well that China won't resort to any compromise in this issue regardless any US pressure.
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