The US has warned China that moving a drilling rig into seas disputed with Vietnam was “provocative”.
In a telephone call, US Secretary of State John Kerry told Chinese Foreign Minister Wang Yi the US had “strong concerns” over recent developments.
Last week, Chinese and Vietnamese ships clashed over the drilling rig that China has placed in waters near the disputed Paracel Islands.
China and Manila are also at odds over overlapping territorial claims. Beijing claims a U-shaped swathe of the South China Sea that covers areas other South East Asian nations say are their territory.
The issue has been rumbling in recent years amid an increasingly assertive stance from China over its claims.
Last week, several collisions were reported between Chinese and Vietnamese vessels in disputed waters as the Vietnamese ships sought to prevent the installation of the Chinese drilling rig.
