BEIJING, May 9 -- China on Friday again urged Vietnam to respect China's sovereign rights and jurisdiction over the Xisha Islands in the South China Sea and stop provocative actions.

Foreign Ministry Spokeswoman Hua Chunying made the remarks at a regular press briefing.

She reiterated that the Xisha Islands are the inherent territory of China and there are no disputes in this area.

The waters of China's drilling operations are only 17 nautical miles from China's Xisha Islands, she said, adding that the operations are about 150 nautical miles from Vietnam.

The operations of Chinese companies in waters off the Xisha Islands fall completely within China's sovereignty, she said, noting that it is untenable for any country to make irresponsible remarks or impede China's normal oil drilling in its territorial waters.

From May 3 to 7, Vietnam dispatched 36 vessels, which rammed Chinese vessels up to 171 times.

The Chinese vessels at the scene are only government and civil vessels, but the Vietnamese side has deployed many armed vessels, according to Yi Xianliang, deputy director-general of the Department of Boundary and Ocean Affairs of China's Foreign Ministry.

In the course of the collisions, the Chinese side also discovered frogmen sent by the Vietnamese side 5 meters from Chinese government vessels, Yi said, adding that the Vietnamese side also placed many fishing nets and large obstacles in the waters, not only posing security threats to Chinese vessels and facilities, but also jeopardizing normal navigation security.

Hua said Vietnam's actions have violated international laws, infringed on China's sovereignty and jurisdiction, and endangered navigational freedom.

It is not conducive to regional peace and stability, she said, adding that the Chinese side had to take additional security measures in response to Vietnam's disruptions to ensure maritime operations and safety of navigation.

U.S. State Department spokeswoman Jen Psaki said on Wednesday that the U.S. opposes provocative or unilateral actions that jeopardize peace and security in the South China Sea.

The U.S. also criticized China on Tuesday by calling its exploration activities "provocative and unhelpful to the maintenance of peace and stability in the region."

Hua said the U.S. has made irresponsible remarks over the maritime issues in recent days, which have encouraged some countries' provocative activities.

She called on the United States to speak and act cautiously, stop making irresponsible remarks, and do more to safeguard regional peace and stability.

Japanese Foreign Minister Fumio Kishida said Friday that Japan regards China's drilling operations in South China Sea waters as "provocative" to regional security, and Beijing should clarify to Vietnam and the international community the basis of its increasing maritime activities.

In response to Kishida's remarks, Hua said relevant Japanese officials should not make comments before figuring out basic facts.

"Japan itself should respect the basic facts and international laws through concrete actions," she added.

She said Japan's aim is to take advantage of China's troubled situation and it cannot hide its true intention of undermining peace and stability by stirring up unilateral provocations in the waters off China's Diaoyu Islands.

"We require the Japanese side to stop any provocative words and actions," she said.