President Trump rebuked Russian president Vladimir Putin for backing an "animal" in Syrian dictator Bashar al-Assad during an interview airing Wednesday on Fox Business.
Trump ordered a missile strike on a Syrian air base last week in retaliation for the Assad regime's chemical weapons attack that killed more than 80 people in rebel-held territory.
While Trump said his administration would not send troops into Syria, he said Assad was "evil" and Putin's backing of him was to blame for the Syrian war.
"Putin is backing a person that's truly an evil person, and I think it's very bad for Russia," he said. "I think it's very bad for mankind. It's very bad for this world ... I really think that there's going to be a lot of pressure on Russia to make sure that peace happens, because frankly if Russia didn't go in and back this animal, you wouldn't have a problem right now."
The comments come as Secretary of State Rex Tillerson meets in Moscow with counterpart Sergei Lavrov, making him the first member of Trump's cabinet to visit Russia. Tillerson said Tuesday to Russia that the Assad era is "coming to an end" and it should back off its support for him.
Lavrov, echoing Putin, warned Tillerson that the U.S. air strike was wrong and should not be repeated. The Russians deny the Assad regime carried out the chemical attack that prompted Trump's strike, but the White House says Russia is covering up for its ally.
Also, a senior official said the U.S. concluded Russia knew ahead of time about the chemical attack.