Chinese officials said that the lighthouses on Chau Vien (Cuarteron) Reef and Gac Ma (Johnson South Reef) in Truong Sa would help maritime search and rescue, maritime security and disaster relief.

However, international experts, diplomats and naval experts said that the two lighthouses show a subtle move of China to support its absurd claims in the East Sea.

Although the US Navy and other countries largely rely on electronic devices to locate their vessels, lighthouses are still used in some cases.

Any action to use lighthouses can fall into a strategy "to promote the claims of China by forcing other countries to recognize Beijing's sovereignty," said Ian Storey, from the Institute of Southeast Asian Studies in Singapore.
 

An illegal lighthouse built by China in Vietnam's Truong Sa Archipelago

"If the naval ships and other vessels from other countries, including the US, are forced to use them [the lighthouses], it may be interpreted as de facto recognition of Chinese sovereignty," Storey said.

Trevor Hollingsbee, a retired naval intelligence analyst at the UK Ministry of Defence, said that the construction of the lighthouses on the renovated reefs was a "dangerous" move by China.

The use of lighthouses is decreasing worldwide, but sometimes vessels have to use them, and it is no exception in the East Sea, said Hollingsbee.

The reference to lighthouses is likely to be recorded in international sea route diaries and journals of the navy of countries. That will help China effectively build a legal occupation picture in the long run, even though it encounters official diplomatic objections from the parties that also make claim in the area.

The lighthouses consolidate Beijing's strategy to gradually "change the status quo in this area," Storey said.

Western naval authorities, both incumbent and retired, said that the introduction of modern electronic navigational equipment, including the US’ GPS system, means that the role of lighthouses was being diminished for all types of seafarers.

But going into the area about several kilometers around reefs or rocks or when electronic devices malfunction, vessels have to rely on lighthouses.

China has renovated seven reefs in Truong Sa in the past two years. The runways and other facilities that China is building on these reefs have worried the US and other countries in the region because Beijing can use these facilities to serve military purposes.

The US has repeatedly not recognized any territorial water claims of China around the artificial islands built on the reefs.

US officials did not confirm or deny the information that the US Navy will soon conduct maritime activities freely within the 12 nautical miles around China’s artificial islands in the East Sea. Secretary of Defense Ash Carter said early this week that the US ships would work anywhere as long as international law allows.

Bill Clinton, a spokesman for the US 7th Fleet, did not mention in detail of the circumstances under which American ships would use China’s lighthouses, but he insisted that the lighthouses "do not affect the ability of the 7th Fleet to operate in international waters in the East Sea."

China has recently changed its tone, seeking to reduce tensions with South East Asian countries, which also have claims in the East Sea. Beijing also said that the artificial islands "would not affect the freedom of navigation in the East Sea."

Mr. Gary Roughead, former chief of the US Navy, said that the size of the ports and airports that China is building in Truong Sa has raised legitimate concerns. He said that tourists do not visit such remote places.