His appointment was confirmed on Tuesday at the Council of State meeting.
The Council is made up of the President and former Presidents among others.
The Council met in Abuja at the Presidential Villa.
The meeting was presided over by President Goodluck Jonathan.
Among those that attended were former Presidents Olusegun Obasanjo and Shehu Shagari; former Head of State, retired General Yakubu Gowon; and former Head of the Interim National Government, Chief Ernest Shonekan.