"We are closely following the situation and developments in the East Sea," Foreign Ministry spokeswoman Le Thi Thu Hang said Thursday, using the Vietnamese name for the waterway.
She was responding to a question about Taiwan’s plan on holding a three-day live-fire drill around Ba Binh Island, internationally known as Itu Aba, beginning November 21.
Taiwan will use 40mm grenade launchers and other weapons in the drill supposed to cover a radius of eight kilometers.
Ba Binh, the largest naturally occurring island in the Truong Sa Archipelago, which Vietnam asserts sovereignty over, is currently occupied by Taiwan.
Hang reiterated that Vietnam has full legal grounds and historical evidence to assert indisputable sovereignty over the Paracel (Hoang Sa) and Spratly (Truong Sa) archipelagoes in accordance with international law.
Taiwan's repeated drills around Ba Binh Island threaten peace, stability, maritime safety and security, create tension and complicate the situation in the South China Sea, she said.