President Donald Trump on Saturday cast doubt on U.S. intelligence showing Russia meddled in the 2016 presidential election, saying Russian President Vladimir Putin is irritated by repeated questions over the matter and calling a trio of former heads of U.S. intelligence agencies “political hacks.”

Speaking to reporters for nearly 30 minutes on Air Force One after several conversations with Mr. Putin earlier in the day, Mr. Trump said he was “not going to get into an argument” with Mr. Putin over the issue.

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