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

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 preplanned test,” Gates told reporters, “and that’s where we left it.”

U.S. officials refused to speculate about why the test flight occurred when it did. Gates said he “took President Hu at his word.”