China on Tuesday reiterated its position opposing any other country that exploits oil and gas resources in Chinese maritime areas without permission of the Chinese government.

"China has always opposed the exploration and exploitation of ocean oil and gas resources in Chinese sea territories without our permission. We have made representations and taken measures to stop these illegal activities," Deng Zhonghua, director general of the department of boundary and ocean affairs with the Foreign Ministry, said in a Web chat hosted by the website of People's Daily.

According to United Press International, Russian natural gas producer Gazprom said it has reached a deal with Vietnam Oil & Gas Group to exploit two gas blocks in the South China Sea.

The two blocks cover two discovered gas and condensate fields with total reserves of 55.6 billion cubic meters of gas and 25 million tons of condensate, Gazprom said.

"We hope relevant countries will work with us, to avoid pulling extra-regional countries into the disputes. We also hope those extra-regional countries will respect and support dialogue and negotiation between China and relevant countries, and try to avoid getting involved," said Chinese Foreign Ministry spokesman Liu Weimin, also on Tuesday, at a regular news briefing.

China has indisputable sovereignty over the islands in the South China Sea and the adjacent waters, and always insists on putting aside our differences and making joint development of ocean oil and gas resources in disputed waters. We would like to discuss this issue with relevant countries for a comprehensive and proper settlement, Deng said.

Chu Hao, a researcher in Vietnamese studies at the China Institute of Contemporary International Relations, said this move signals that Vietnam is bringing in Russia, which is an extra-regional country, to balance China's influence in disputes concerning the South China Sea.

"Since Vietnam has always taken it as a policy, and the Kremlin is trying to commit to the revitalization of Russia in East Asia, it's normal to see the two countries signing the deal. They each just take what they need," said Chu.

By increasing overall national strength, great changes have taken place in our environment at home and abroad, and it is an important reason for the hype surrounding disputes over the South China Sea, Deng said. "It is part of our growing pains."

Indian external affairs minister S.M. Krishna said last week that the South China Sea is the property of the world. He said: "Those trade ways must be free from any national interference. They have to be used for increasing trade-related activities among nations, which come within the range of the South China Sea."

All countries have fully enjoyed freedom of navigation in the South China Sea and it is an obvious fact, Deng said. The booming economies of East Asia and Southeast Asia in the past few years illustrate that the freedom of navigation has not been affected in the South China Sea.

"As for some extra-regional countries that are keen to inflate the freedom of navigation and security issues in the South China Sea, they are, in fact, using it as an excuse to intervene in the dispute, and we resolutely oppose that," he said.

Now China and India are both rising in Asia, and India regards China as its biggest strategic rival in this region, said Chu. Krishna's remarks could be seen as a move to further heat up the disputes in order to contain China and prevent the country's rise.