The U.S. White House says that President Barack Obama called Afghan President Hamid Karzai before leaving Bagram Airbase May 25 to praise him for progress by security forces.
Washington says that Obama and Karzai spoke for 15 to 20 minutes.
The phone call came despite Karzai's earlier declining an invitation to meet with the U.S. president at Bagram.
Obama made a surprise one-day visit to U.S. troops at Bagram on May 25 to celebrate the U.S. Memorial Day holiday with them.
The U.S. president said at Bagram he is hopeful Washington will sign a bilateral security agreement with Kabul after a new Afghan president is sworn in.
A second round of Afghanistan's presidential poll is scheduled for June 14.
The candidates running to succeed Karzai say they will sign.
Based on reporting by dpa and Reuters