BEIJING - Breaking 13 days of silence, China confirmed yesterday that it fired a guided missile into space to destroy one of its own satellites in a test of antisatellite technology that generated protests from the United States and other nations.

A Foreign Ministry spokesman, Liu Jianchao, said the United States and other governments now had been informed about the secret test through diplomatic channels and emphasized that it did not mean China had abandoned its long-standing opposition to the military use of space.

"I should stress at this time that the test was not targeted against any country and does not pose a threat to any country," Liu told a ministry briefing. He added that he knew of no plans for another such test by the Chinese military.

The Chinese test shot, which culminated in destruction of a defunct weather satellite 537 miles above Earth, was detected by U.S. monitors Jan. 11, but the Chinese government refused to discuss it. The test raised concern in Washington, where officials and analysts interpreted it as a signal by China that U.S. military satellites could be vulnerable to attack.

With the U.S. military heavily reliant on satellites for reconnaissance, navigation, weapons guidance systems and antimissile defenses, Chinese ability to shoot down satellites in space could pose an added threat in the event of hostilities over Taiwan. In addition, China's newly demonstrated ability could threaten Taiwan's own satellites monitoring Chinese short- and medium-range missile deployments along the Taiwan Strait.

U.S. officials said they were also dismayed by the Chinese test because the United States and Russia, after testing antisatellite technology in the 1980s, more recently have abstained from further tests, partly because they create a cloud of debris that could damage nearby satellites. Liu declined to address questions on that danger.

At the United Nations, China consistently has advocated peaceful space development and pushed for an international agreement to prevent outer space from becoming the theater for an arms race.

In that light, Liu was asked whether the antisatellite test violated the spirit of China's proclaimed position and, in any case, why China kept silent for nearly two weeks while officials around the world were discussing it on the basis of U.S. intelligence reports.

"We have nothing to hide," he responded. "After the relevant parties expressed their concerns, we made our response about the test quickly. We stressed that China opposes weaponization and an arms race in outer space. Our position has not changed."