The war of words between China and the Philippines over disputed islands in the South China Sea escalated on Tuesday, ahead of a key regional security dialogue in Indonesia. China’s embassy in the Philippines warned that plans by five Filipino lawmakers to visit the disputed Spratly archipelago — in what Manila calls the the West Philippine Sea — could damage bilateral ties. “It… serves no purpose but to undermine peace and stability in the region and sabotage the China-Philippines relationship,” the embassy said of the one-day trip scheduled for Wednesday.