This is seen as the first concrete move included in the US’s plan to conduct regular patrol activities in the East Sea.
“ We are conducting routine operations in the East Sea in accordance with international law. US forces operate in the Asia-Pacific region on a daily basis, including in the East Sea" the official said.
The official also stressed that these operations are "distinct from the question of sovereignty over these islands."
Meanwhile, Reuters said the patrol carried out by the destroyer USS Lassen will near Su Bi (Subi) Reef and Vanh Khan (Mischief) Reef on the Truong Sa archipelago.
Additional patrols would follow in the coming weeks.
Earlier, the Barack Obama administration repeatedly affirmed that the US will exercise the right to freedom of navigation at any international waters where international law allows, including the East Sea.
Vietnam has adequate legal and historic foundations proving its sovereignty over the Truong Sa and Hoang Sa (Paracel) archipelagoes, including Su Bi and Vanh Khan Reefs which China occupies by force.
On October 15, Vietnam Foreign Ministry’s spokesperson said in response to the information that the US will sail a warship within 12 nautical miles near man-made islands that China built illegally in Vietnam’s Truong Sa archipelago, that countries in and outside the region have the responsibility to contribute to maintaining and enhancing peace, stability as well as navigation and aviation security, safety and freedom in the region on the basis of the strict observance of international law.