Secretary of State Rex Tillerson has wrapped up a visit to Moscow, where he met with Russian President Vladimir Putin and Russian Foreign Minister Sergey Lavrov. The meetings come at a time of increased tension between Washington and Moscow. On Wednesday during a press conference with NATO’s secretary general, President Trump said relations with Russia had reached a new low point.

President Donald Trump: “It would be wonderful, as we were discussing just a little while ago, if NATO and our country could get along with Russia. Right now we’re not getting along with Russia at all. We may be at an all-time low in terms of relationship with Russia. This has built for a long period of time.”

Trump’s comments came a day after the White House accused Russia of attempting to cover up the role of the Syrian government in the recent chemical attack in Syria that killed 87 people. Russia has rejected the claim, saying the U.S. has been too quick to blame Syrian President Bashar al-Assad. At the United Nations, Russia blocked a Security Council resolution Wednesday to denounce the chemical attack and to call on Assad’s government to cooperate with an international probe. Meanwhile, Russia has accused the United States of violating international law by bombing a Syrian air base last week.