WARSAW — President Trump again cast a skeptical eye on intelligence community assessments that Russia interfered with the 2016 presidential election, saying Thursday while on a visit to Poland that "nobody really knows for sure" what happened.

"Well, I think it was Russia and I think it was other people in other countries who also interfere," he said at a press conference in Warsaw with the president of Poland. "I wont be specific, but I think a lot of people interfere."

Trump has made such pronouncements to varying degrees before. But this one comes on the eve of his first face-to-face meeting Friday with Russian President Vladimir Putin at a Group of 20 summit in Hamburg, Germany. Intelligence agencies say Putin personally directed an effort to boost Trump's candidacy through the theft of emails belonging to the Democratic National Committee and party leaders and release to websites such as WikiLeaks.

And the remarks follow a Washington Post report last month detailing former President Obama's administration's stumbling attempts to deal with Russian meddling during last year's campaign. The CIA gave Obama an urgent report three months before the election. "That's a lot of time. He did nothing about it," Trump said.

"They say he choked. I don’t think he choked," Trump added. "I think what happened is he thought Hillary Clinton was going to win the election, and he chose not to do anything about it. If he thought I was going to win, he would have done something about it."

Trump also compared the intelligence about Russian interference with the faulty assessment that Iraq had weapons of mass destruction in 2002, which provided President Bush with a justification to go to war.

"Guess what, they were wrong, and that led to one big mess," he said.

Trump answered questions with Polish President Andrzej Duda at Warsaw's Royal Castle, his first stop on a two-city European tour in which he will meet central European leaders and attend the summit in Hamburg. It was his first news conference in almost a month — and the first time he answered questions on foreign soil.

The press event also came as Trump faces several pressing questions on foreign policy, including his response to North Korea's latest test of a multi-stage missile capable of reaching U.S. territory and a German-driven agenda at the G-20 summit that's opposed to Trump's policies on trade, immigration and climate change.

The president used the news conference to call on nations to confront North Korea’s "very, very bad behavior" and vowed consequences for the missile launch. In a speech later Thursday in Warsaw, Trump is expected to say that Western civilization needs to be defended from terrorism and extremism, according to excerpts from the address.

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