China is facing international criticism over a weapons test it reportedly carried out in space last week.
The missile was reportedly launched near Xichang Space Centre
Japan has expressed concern, as have the US and Australia.
It is thought that the Chinese used a ground-based medium-range ballistic missile to destroy a weather satellite that had been launched in 1999.
Correspondents say this is the first known satellite intercept test for more than 20 years. China's foreign ministry refused to confirm or deny the report.
While the technology is not new, it does underline the growing capabilities of China's armed forces, according to the BBC's Dan Griffiths in Beijing.
Space arms race?
Late on Thursday, US National Security Council spokesman Gordon Johndroe confirmed an article in the magazine American Aviation Week and Space Technology, which reported that the test had taken place.
The report said that a Chinese Feng Yun 1C polar orbit weather satellite was destroyed by an anti-satellite system launched from or near China's Xichang Space Centre on 11 January.
The test is thought to have occurred at more than 537 miles (865km) above the Earth.
Foreign ministry spokesman Liu Jianchao said: "I can't say anything about the reports. I really don't know."
But he added: "China advocates the peaceful use of space and opposes the weaponisation of space, and also opposes any form of arms race."
Japanese Prime Minister Shinzo Abe said he had asked China for an explanation and said nations "must use space peacefully".
Japanese Foreign Minister Taro Aso said Beijing should have given Tokyo advance notice.
Mr Johndroe said the US "believes China's development and testing of such weapons is inconsistent with the spirit of co-operation that both countries aspire to in the civil space area".
CHINA IN SPACE
China first launched a manned space mission in 2003 - the third nation to do so after the US and Russia
Chinese astronauts aim to perform a spacewalk as early as next year
Until now, the US and Russia have been the only nations to shoot down space objects
China insists its space programme is of no threat, but other nations are wary
China says it spends $500m on space projects. NASA is due to spend $17bn in 2007
Australian Foreign Minister Alexander Downer said Australia did not want to see "some sort of spread, if you like, of an arms race into outer space".
There are already growing international concerns about China's rising military power.
While Beijing keeps its defence spending a closely-guarded secret, analysts suggest that it has grown rapidly in recent years.
The test, if confirmed, would mean that China could now theoretically shoot down spy satellites operated by other nations.
It would be the first such test since the 1980s, when both the US and the Soviet Union destroyed satellites in space.
These tests were halted over concerns that the debris they produced could harm civilian and military satellite operations.
The same concerns have been raised about this latest reported test.
American Aviation Week and Space Technology said the move could have left "considerable space debris in an orbit used by many different satellites".
While the US may be unhappy about China's actions, the Washington administration has recently opposed international calls to end such tests.
It revised US space policy last October to state that Washington had the right to freedom of action in space, and the US is known to be researching such "satellite-killing" weapons itself.