The Philippine foreign minister on Monday demanded in an expletive-laced message on Twitter that China's vessels get out of disputed waters, marking the latest exchange in a war of words with Beijing over its activities in the South China Sea.

The comments by Teodoro Locsin, known for making blunt remarks at times, follow Manila's protests for what it calls the "illegal" presence of hundreds of Chinese boats inside the Philippines 200-mile (320km) Exclusive Economic Zone (EEZ)...