A U.S. warship sailed within 12 nautical miles of an island claimed by Beijing in the South China Seas, in an operation intended to underscore America’s right to access the disputed waters, the Pentagon said.

A U.S. warship sailed within 12 nautical miles of an island claimed by Beijing in the South China Seas, in an operation intended to underscore America's right to access the disputed waters, the Pentagon said.

"We conducted a freedom of navigation operation in the South China Sea earlier tonight," Pentagon spokesman Jeff Davis said in statement issued late Friday U.S. time.

He said the operation was carried out near Triton Island in the Paracel Islands, "to challenge excessive maritime claims of parties that claim the Paracel Islands."

Davis said that the USS Wilbur was the guided missile destroyer used in the operation, and that no Chinese ships were in the vicinity at the time.

The waters of the South China Sea have been the subject of tense territorial disputes in the region, the Pentagon spokesman noted.

He added that Washington did not notify any of the countries laying claim to the islands that it intended to enter the territorial waters before embarking on the mission.

"This operation challenged attempts by the three claimants -- China, Taiwan and Vietnam -- to restrict navigation rights and freedoms around the features they claim by policies that require prior permission or notification of transit within territorial seas," Davis said.

"The excessive claims regarding Triton Island are inconsistent with international law as reflected in the Law of the Sea Convention. This operation was about challenging excessive maritime claims that restrict the rights and freedoms of the United States and others, not about territorial claims to land features," he said.

Davis added: "The United States takes no position on competing sovereignty claims between the parties to naturally-formed land features in the South China Sea. We do take a strong position on protecting the rights, freedoms, and lawful uses of the sea and airspace guaranteed to all countries.  All maritime claims must comply with international law."