In his remarks before the meeting, Obama first thanked Borisov for Bulgaria's role in the NATO and its contribution to the war in Afghanistan. He also thanked Borisov for his "very diligent investigation" into the bombing that killed five Israeli tourists and a local bus driver in Bulgaria in July.

"The security teams in Bulgaria have worked very hard and cooperatively in bringing the perpetrators to justice," said Obama.

In response, Borisov said that people in Bulgaria were "deeply moved" at Obama's telephone call wherein the U.S. president conveyed condolences for the Bulgarian citizen as well as the Israeli nationals who were killed in the July bombing.

Borisov said he appreciated Obama's mentioning of Bulgaria's contribution to the wars in Iraq and Afghanistan and also thanked Obama for cooperation with the United States in areas including national security, counterterrorism and combating organized crime.

The two leaders would discuss the NATO's transition in Afghanistan during their meeting, according to Obama.