The United States and China have taken tentative first steps toward cooperation on civilian space projects.

The visit by Michael Griffin, the top official of the U.S. National Aeronautics and Space Administration, represents a turning point in Washington's attitude toward China's space program.

The United States has been reluctant to cooperate with China's secretive, military-based space efforts.

Griffin told reporters Monday that NASA is still unable to cooperate with the military side of China's space efforts. But he said his visit is a step toward lessening the distance between the two countries on space cooperation.

Asked if he had gotten much access to the Chinese agency's operations, Griffin said he did not.

But, he says, his expectations were limited from the start.

"This is a get-acquainted visit. This is an exploratory visit," he explained. " This is a first date, if you will. We're just (on) an exploratory visit."

Griffin said he and Chinese officials had agreed to hold discussions at least once a year. The two sides are also looking at setting up a working group to share information on earth science research, climate studies, and scientific missions, among other things.

China has in recent years accelerated its space exploration efforts. In 2003, it became the third nation after the former Soviet Union and the United States to put a human in orbit. The second Chinese manned space flight took place last October.