BEIJING (Reuters) - China is concerned by U.S. plans to shoot down an ailing spy satellite and is considering what "preventative measures" to take, the Foreign Ministry said on Sunday.

"The Chinese government is paying close attention to how the situation develops and demands the U.S. side fulfill its international obligations and avoids causing damage to security in outer space and of other countries," spokesman Liu Jianchao said.

President George W. Bush has decided to have the Navy shoot the 5,000-pound (2,270 kg) satellite with a modified tactical missile after security advisers suggested its re-entry could lead to a loss of life, U.S. officials said on Thursday.

"Relevant departments in China are closely watching the situation and studying preventive measures," Liu said in a brief statement posted on the Foreign Ministry's Web site

On Saturday, Russia's Defense Ministry said the U.S. plan could be used as a cover to test a new space weapon.

It will be the first time the United States has conducted an anti-satellite operation since the 1980s. Russia also has not conducted anti-satellite activities in 20 years.

China launched a ground-based missile into an obsolete weather satellite in January 2007, drawing international criticism and worries inside the Pentagon that Beijing has the ability to targetcritical military assets in space.