When Gates mentioned the test in an afternoon meeting with President Hu Jintao at the Great Hall of the People, it was initially clear that neither Hu nor any of the other Chinese civilian officials present were aware that it had occurred, according to a senior U.S. Defense Department official.

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After confirming the test flight, Hu told Gates that it was not timed to coincide with his visit.

“He said that the test had absolutely nothing to do with my visit and had been a pre-planned test, and that’s where we left it,” Gates told reporters shortly after the meeting. Gates added that he “takes President Hu at his word.”

U.S. officials refused to speculate about why the test flight occurred when it did.