WASHINGTON - In a phone call with his Russian counterpart Vladimir Putin on Monday, U.S. President Donald Trump offered his full support to Russia in responding to an attack in St. Petersburg Metro, the White House said.
Trump spoke with Putin to condemn the attack and expressed "his deepest condolences to the victims and their loved ones, and to the Russian people," the White House said in a statement.
"President Trump offered the full support of the U.S. government in responding to the attack and bringing those responsible to justice," the statement said.
Both leaders "agreed that terrorism must be decisively and quickly defeated," it added. 
At least 11 people were killed and dozens of others were wounded on Monday in an explosion in a train carriage on the runway between the metro stations of Technological Institute and Sennaya Ploshchad (Square) in St. Petersburg.
Russian officials described the bombing as an act of terror. The exact cause of the attack remain unknown pending an official investigation.
Putin has laid flowers at the entrance of the Technological Institute station, expressing his condolences to the families of the victims. (Xinhua)