China hit back at the United States over the disputed South China Sea on Tuesday, after US Secretary of State John Kerry said recent Chinese moves in the resource-rich waters were "provocative".
Tensions rose last week after China moved a giant oil rig into an area also claimed by Vietnam. Each country accused the other of ramming its ships near the disputed Paracel Islands.
China claims almost the entire South China Sea, rejecting rival claims to parts of it from Vietnam, the Philippines, Taiwan, Malaysia and Brunei.
"He (Kerry) said China's introduction of an oil rig and numerous government vessels in waters disputed with Vietnam was provocative," US State Department spokeswoman Jen Psaki said, referring to a telephone call between Kerry and Chinese Foreign Minister Wang Yi in which North Korea was also discussed.
"He urged both sides to de-escalate tensions, ensure safe conduct by their vessels at sea, and resolve the dispute through peaceful means in accordance with international law."
China's foreign ministry said there certainly had been provocative moves in the South China Sea, but that China was not the guilty party and repeated that it was the United States' fault for encouraging such behaviour.
"We hope that the US side can carefully reflect - if they really hope for the Pacific Ocean to be peaceful, what kind of role do they actually want to play?" spokeswoman Hua Chunying told a daily news briefing.
Hua said that Wang urged Kerry to "objectively and fairly" look at the South China Sea issue, and "act and speak cautiously".
China says that the South China Sea issue should be resolved via direct talks between the parties concerned, and has bristled at what it sees as unwarranted US interference.
China has also looked askance at the US "pivot" back to Asia, especially Washington's efforts to boost existing military links with Tokyo and Manila.
In separate remarks to visiting Singapore Foreign Minister K. Shanmugam, Kerry said the United States was deeply concerned by China's "aggressive act".
"We are particularly concerned - all nations that are engaged in navigation and traffic within the South China Sea, the East China Sea, are deeply concerned about this aggressive act," Kerry said in the Monday meeting.
"We want to see a code of conduct created; we want to see this resolved peacefully through the Law of the Sea, through arbitration, through any other means, but not direct confrontation and aggressive action," Kerry added, according to a transcript of his comments released by the State Department.
Speaking to fellow leaders of the Association of Southeast Asian Nations at a summit on Sunday, Prime Minister Nguyen Tan Dung said Vietnam had acted with "utmost restraint" and used all means of dialogue to request China remove the rig.
Dung said China was slandering his country and committing dangerous violations.
However the communiqué issued at the end of the summit by the 10-nation ASEAN group contained no criticism of China.
Vietnamese state media said that Vietnamese and Chinese ships had again used water cannon on each other on Monday, though there were no injuries.
Chinese spokeswoman Hua would neither confirm nor deny the new face-off, repeating that China was urging Vietnam to "end its provocative actions" and withdraw its ships.
Kerry and Wang also reaffirmed the US and China's shared commitment to work towards North Korean denuclearization, Psaki said, after North Korea on Saturday renewed a threat to set off an atomic device amid heightened concern over its attempts to build a nuclear arsenal.
"China is committed to realizing denuclearization of the Korean peninsula, safeguarding peace and stability of the Korean peninsula and resolving relevant issues through dialogue and consultation," Wang was cited as saying in a statement posted to the ministry's website.
North Korea is under heavy sanctions imposed by several UN resolutions adopted beginning in 2006 but has defied pressure to abandon its missile and nuclear programs. It last conducted a nuclear test in February last year.