"This decision reflects the Administration's commitment to closing the detention facility at Guantanamo Bay," State Department spokesperson Jen Psaki told reporters yesterday.
Sloan, who has served in senior government positions in both Democratic and Republican administrations, would resume duty on July 1.
The continued operation of Guantanamo is not efficient, effective, or in the interests of US national security, Psaki said referring to a recent statement by President Obama in this regard.
Currently, there are 166 detainees at the Guantanamo detention centre, down from 242 when Obama had taken over as the President in January 2009.
A hunger strike by more than 100 of the 166 prisoners protesting their conditions and indefinite confinement has prompted the fresh calls for closure of the facility run by military.