TOKYO — Secretary of State Mike Pompeo shot back at North Korean officials for characterizing American diplomatic behavior as gangster-like, saying on Sunday that if that was true, then “the world is a gangster.”

Mr. Pompeo was referring to comments made Saturday by North Korea’s Foreign Ministry that accused the Trump administration of pushing a “unilateral and gangster-like demand for denuclearization” and called it “deeply regrettable.” The statement came just hours after Mr. Pompeo left North Korea after two days of meetings that he had called “productive.”

In his remarks on Sunday, Mr. Pompeo noted that the United Nations had agreed to place sanctions on North Korea to try to stop its nuclear and missile programs, saying, “It was a unanimous decision at the U.N. Security Council about what needs to be achieved.”

Mr. Pompeo blamed the media for the stark differences in how he assessed the talks compared with how North Korea’s Foreign Ministry viewed them.