Robert Gates said Donald Trump's pronouncements on international affairs have had "some contradictions." | Getty Gates slams Trump's go-it-alone foreign policy 'He seems to think that he has all the answers'

Former Defense Secretary Robert Gates said Donald Trump's approach to foreign policy is inconsistent and overconfident.

"He seems to think that he has all the answers and that he doesn't need any advice from staff or anybody else," Gates, who served under Presidents George W. Bush and Barack Obama, said in an interview with John Dickerson that aired Sunday on CBS' "Face the Nation."


"And that he knows more about these things than anybody else," Gates added in discussing the presumptive Republican presidential nominee. "And doesn't really feel the need to surround himself with informed advisers."

Gates said Trump's pronouncements on international affairs have had "some contradictions," such as imposing tariffs on Chinese imports while looking to Beijing to help rein in North Korea.

"I have no idea what his policy would be in terms of dealing with ISIS," Gates said. "I worry a little bit about his admiration for Vladimir Putin."

As for Trump's likely rival, Hillary Clinton, Gates said he believes she can handle the job of president and doesn't let politics interfere with her judgment.

"Generally speaking, she is more hawkish than President Obama," he said.