A Chinese ship, left, shoots water cannon at a Vietnamese vessel, right, while a Chinese Coast Guard ship, center, sails alongside in the South China Sea, off Vietnam's coast, Wednesday. Pic: AP.

UNITED NATIONS (AP) — Secretary-General Ban Ki-moon is urging China and Vietnam to exercise “utmost restraint” and resolve their dispute over contested South China Sea waters peacefully.

The U.N. chief urged both countries to settle their differences through dialogue following escalating tensions in the South China Sea in the last few days, U.N. deputy spokesman Farhan Haq said Friday.

Chinese and Vietnamese ships have been jostling each other since China deployed a deep-sea drilling rig last weekend in the disputed waters.

China insisted Thursday it had every right to drill for oil off Vietnam’s coast and warned Vietnam to leave the area. The United States has warned both sides to de-escalate tensions and urged China to clarify its claims to the territory.