President Donald Trump has scheduled another phone call with Russian President Vladimir Putin.
The White House did not immediately respond to questions Monday about the expected topics of the conversation.
But the bloody civil war in Syria and Putin's continued backing of Syrian President Bashar Assad loom large.
Trump and Putin have spoken several times since Trump's election, including last month following an attack in St. Petersburg, which Trump condemned.
Trump said last month that U.S.-Russian relations "may be at an all-time low." It was a reversal from the rhetoric during his campaign, when Trump said he hoped he and Putin could work together in the fight against terrorism.
FBI and congressional investigations continue into the Trump campaign's contacts with Russia and Russia's meddling in the election.