White House press secretary Jen Psaki on Monday said the US is “concerned” about China’s military buildup but that “we welcome stiff competition” after the Communist nation’s reported test of a hypersonic missile capable of delivering a nuclear bomb.

Word of the missile test stunned the US military. It came close to hitting its target after circumventing the globe — demonstrating a significant advance in China’s military capabilities, according to a report. The Chinese government claims it was a space mission, not a missile test.

“Generally speaking, we have made clear we are concerned about the military capabilities that the PRC continues to pursue,” Psaki said. “And we have been consistent in our approach with China. We welcome stiff competition, but we do not want that competition to veer into conflict. And that is certainly what we convey privately as well.”