US Army B-52 bomber (Source: Reuters)

"On the morning of December 10, two B-52s entered the airspace of the Spratly Islands and nearby areas without permission from competent authorities," the Chinese Ministry of Defense said in a statement, brazenly calling Vietnam's Truong Sa archipelago the Nansha Islands, as Beijing calls them.

Previously, the Wall Street Journal quoted the Pentagon as saying that while on a mission, a US B-52 bomber mistakenly flew into the 2-nautical mile area around an artificial island built by China in the East Sea.

According to the newspaper, one of the two aircraft carrying out the above mission flew closer than expected in the area around Chau Vien Reef (called Hoa Duong Tieu by China) in the Truong Sa archipelago.

The Wall Street Journal also said that the Pentagon is currently investigating why the B-52 aircraft flew so close to the reef.

Previously, on November 12, the Pentagon announced that a US B-52 aircraft had flown near artificial islands built by China in the East Sea.

Last October, in response to a reporter's question about Vietnam's reaction to the recent US sending ships through some geographical structures in Vietnam's Truong Sa archipelago, Vietnamese Foreign Ministry Spokesperson Le Hai Binh stated: "As a country with sovereignty over the Hoang Sa and Truong Sa archipelagos in the East Sea and a member of the 1982 United Nations Convention on the Law of the Sea, Vietnam respects the freedom of navigation and overflight in the East Sea on the basis of relevant provisions of the Convention and in accordance with the regulations of coastal states."

"Vietnam calls on relevant parties to actively contribute to maintaining peace, stability, security and safety of navigation and aviation in the East Sea on the basis of international law, including the 1982 United Nations Convention on the Law of the Sea and the Declaration on the Conduct of Parties in the East Sea (DOC)"./.

According to Vietnam+