"Putin expresses his profound condolences for the British people and condemns the terrorist attack carried out hours ago in London," Kremlin spokesman Dmitry Peskov told Russian news agencies.
"This crime shocks with its cruelty and cynicism," the Russian leader was quoted as saying later in a telegram to British Prime Minister Theresa May.
"The Russian president expressed his certainty that the common response to what has happened should be an increase in combined efforts in the fight against the forces of terror around the world," the Kremlin said.
The trio were shot dead by police at the scene.
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