China is warning that Vietnam's offer to its citizens of a cruise to islands in the South China Sea "violates" Chinese sovereignty.
The comment came after Vietnam said it would offer scores of its citizens a cruise to China's Nansha islands that are under its control.
It's reported that 180 Vietnamese will take part in the voyage later this month with each paying 800 US dollars.
Chinese Foreign Ministry spokesman Hong Lei expressed strong disatisfaction with the move.
"China has indisputable sovereignty over the Nansha islands and surrounding waters. Vietnam's actions violate China's sovereignty. We demand that Vietnam respect China's sovereignty, not take actions that complicate or magnify the situation, and make proper efforts to safeguard the peace and stability of the South China Sea."
Disputes over the Nansha islands escalated between the two sides about one year ago after China deployed oil rig No. 981 in the area.
The tensions began to show signs of easing following recent visits by senior Vietnamese officials, including Nguyen Phu Trong, general secretary of the Central Committee of the Communist Party of Vietnam.
