Washington (CNN) President Donald Trump on Monday repeatedly highlighted the Saudi King's denial of involvement in the disappearance of Jamal Khashoggi, at one point offering up an alternative theory that "rogue killers," rather than agents of the Saudi regime, were involved.

Trump also said he was dispatching Secretary of State Mike Pompeo to meet with King Salman.

"It wasn't like there was a question in his mind. The denial was very strong," Trump told reporters outside the White House, adding that the King "firmly denied any knowledge" of what happened to Khashoggi, a Washington Post journalist and Saudi dissident.

The President said he spoke with Salman on the phone Monday, and said that after the call, he believed "rogue killers" may have killed Khashoggi, suggesting that was a possible explanation Salman offered up during their conversation.

"It sounded to me like maybe these could have been rogue killers, who knows. We are going to try to get to the bottom of it very soon," Trump said. "But his was a flat denial."

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