BEIJING - The Defense Ministry brushed aside reports on Wednesday about Russia's refusal to sell China cables used to catch and slow planes on aircraft carriers, saying all major equipment on China's carrier is developed domestically.

"The reports are totally groundless," ministry spokesman Yang Yujun said at a monthly news conference. He was asked about a report in November carried by Asian Defence, a Toronto-based monthly, that claimed Russia refused to sell the cables to China because of strategic concerns.

"All the major systems and equipment on our aircraft carrier, including the arresting cables, are developed or refit by us," Yang said.

The carrier is reported to have started a third round of sea trials on Dec 20, which should take about nine days.

Yang said the carrier is currently engaged in scheduled sea trials, adding that the tests and training at sea is a long-term process.

Li Jie, a research fellow at the Naval Military Studies Research Institute, said advanced military powers are not likely to sell their technologies to China for its carrier out of their own national interests.

"China has to develop its capability by itself because major military powers don't want to lose their military advantages by selling technologies," he said.

He also said, successes aside, China's carrier development is still in the first stage. At least five to eight years are needed to fully develop a carrier system.

At the news conference, Yang also talked of China's satellite positioning system, Beidou, which started operation on Tuesday.

"As we all know, international satellite navigation systems are for military and civilian use," Yang said when asked about Washington's concern that Beidou will pose security threats to the United States.

"China is building the Beidou satellite navigation system to satisfy diversified civil demands, and it is good for our national defense development."

Yang added that Beijing has long been making efforts to push forward integration between Beidou and the world's other major systems of that kind for the development of global satellite navigation.

"I think the concerns are needless."

Beidou, or Big Dipper, the domestic version of the US Global Positioning System (GPS), started providing navigation, positioning and timing data on a pilot basis to China and the neighboring regions for free on Tuesday.

With the system operational, China is the third in an elite group, along with the US and Russia, to develop a satellite navigation system.

Russia has finished rebuilding its GLONASS system, which achieved a 24-satellite constellation in 1996 but succumbed to funding problems.

The European Union and the European Space Agency are building the Galileo satellite navigation system.

Beidou, with six more satellites to be launched next year, will cover the globe by 2020. It will then be as accurate as GPS globally and superior to GPS in the Asia-Pacific region.

Li Qinggong, deputy secretary of the China Council for National Security Policy Studies, said satellite positioning systems normally have military and civilian uses.

He said the civilian and military applications require two separate operating systems under the same positioning platform, thus military information leaks and theft are impossible along with the integration among the major satellite systems.

"China's Beidou still has a long way to go to perfect itself while cooperation with other major systems in civilian use is possible and crucial in the future," he said.

Zhao Shengnan contributed to this story.

China Daily