U.S. President Barack Obama is to bestow the country's highest civilian honor - the Presidential Medal of Freedom - to 16 people for their significant contributions to the nation and world.

In a statement Thursday, President Obama said that although the honorees work in a range of fields, each shares one trait - they are "an agent of change."

The recipients include world-renowned physicist Stephen Hawking; Dr. Muhammad Yunus, a Nobel Peace Prize laureate who pioneered "micro-loans"; and Archbishop Desmond Tutu, the South African anti-apartheid activist and Nobel Peace Prize winner.

Also to be honored in the August 12 White House ceremony are former U.S. Supreme Court Justice Sandra Day O'Connor, the first woman to sit on the high court; long-time U.S. Senator Edward Kennedy; and U.S. actor Sidney Poitier, a top African American movie star in the 1950s and 1960s.

Other recipients are to include Ireland's first female president, Mary Robinson, and Native American, Dr. Joseph Medicine Crow, who wrote key works on Native American history and culture.  

The Presidential Medal of Freedom is granted to individuals whose work contributes to the security or national interest of the United States, world peace, culture or other significant endeavors.