The United States has confirmed that South Korea's president will be excluded from its eavesdropping targets, a government source said Sunday.

U.S. President Barack Obama announced reform measures for the National Security Agency earlier this month, including a promise not to eavesdrop on the heads of state or governments of close U.S. friends and allies unless there is a compelling national security purpose.

South Korea has since inquired the U.S. about the measures and has been told that South Korea is among the "close U.S. friends and allies," the source. The response effectively means that the U.S. will not listen in on the South's president.

The U.S. is expected to offer official explanations on the NSA reform measures.

The reform measures came after Washington received intense international criticism following revelations that the NSA eavesdropped on the phone conversations of 35 world leaders. Press reports said German Chancellor Angela Merkel was one of those targeted. (Yonhap News)