The American and Russian presidents spoke on the phone for 90 minutes on Saturday after Russia's parliament voted unanimously to deploy troops in Ukraine, defying warnings from Western leaders not to intervene.

In his conversation with Russian President Vladimir Putin, U.S. President Barack Obama expressed "his deep concern over Russia's clear violation of Ukrainian sovereignty and territorial integrity." Mr. Obama urged Russia to de-escalate tensions by withdrawing its forces back to bases in Crimea and to refrain...