The White House said the two presidents agreed terrorism must meet a swift end. It was not immediately clear who was behind the explosion on the St. Petersburg metro, although the Russian prime minister described it as a "terrorist act."
The official call between the two leaders was the first since shortly after Trump took office -- when Trump spoke with Putin as well as four other world leaders in the same day. Putin also congratulated Trump hours after his electoral victory in November.
The two have offered warm remarks towards one another in the past, and Trump has spoken about a desire to establish better relations with Russia, particularly in the fight on terror.
The US intelligence community has accused Russia of attempting to influence the presidential elections to favor Trump, and FBI Director James Comey publicly revealed last month his agency was investigating the Trump campaign for potential collusion with the Russians to affect the race.
Trump has called the entire matter a "hoax," and Putin has personally denied any improper behavior or connections.
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