President Trump and Russian President Vladimir Putin spoke by phone Wednesday, the White House confirmed in a two-sentence readout later that night. The readout was released hours after Russia had given notice of the call.

According to the White House, Mr. Trump "expressed concern over the vast wildfires afflicting Siberia" and the leaders "discussed trade between the two countries. But what else they discussed is unclear, and the White House made no mention of any discussion of Russian police using force against Russian protesters. The White House did not say whether the U.S. or Russia initiated the call — the Kremlin claims the U.S. did.

Large-scale forest fires have regularly ravaged Siberia, but this year's fires are particularly devastating, with potential for a long-term impact on the environment. More than 7.9 million acres had burned as of earlier this week.

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The president is frequently criticized for his hesitation to criticize the Russian leader, despite Russian meddling in the 2016 presidential election and according to former special counsel Robert Mueller, ongoing meddling in U.S. politics.

When Mr. Trump met with Putin during the G20 summit in June, the president joked with Putin not to meddle in the election.

When Mr. Trump last tweeted about Putin, he touted the two countries' potential for a great relationship.

"Very good call yesterday with President Putin of Russia," the president tweeted after the two spoke in May. "Tremendous potential for a good/great relationship with Russia, despite what you read and see in the Fake News Media. Look how they have misled you on 'Russia Collusion.' The World can be a better and safer place. Nice!"