President Obama and German Chancellor Angela Merkel urged Russia to take immediate steps to deescalate the unrest in Ukraine.
The leaders spoke on a call Thursday about diplomatic efforts to secure a lasting ceasefire "that would be respected by separatists and fully supported by Russia," the White House said in a statement.
Obama and Merkel agreed that the U.S. and Europe should impose costs on Russia if it does not deescalate the crisis quickly.
They also discussed nuclear negotiations with Iran.
Merkel spoke to Putin Thursday as new peace talks are encouraged to start no later than Saturday, according to the Associated Press.