The Nigerian Army performed a symbolic lowering and hoisting of the command flag at Army Headquarters as Lt .-Gen. Olufemi Oluyede assumed command as the 24th chief of army staff.
The ceremony took place on Monday.
President Bola Tinubu appointed Mr Oluyede on October 30 in an acting capacity following the death of his predecessor, Lt.-Gen. Taoreed Lagbaja.
The chief of defence staff, Gen. Christopher Musa, had, on November 1, handed him the insignia of office in an unusual fashion in line with the Armed Forces Act.
The symbolic lowering and hoisting of the command flag, which signifies the beginning of his tenure, came after the Senate and House of Representatives confirmed his appointment.
Until his appointment, Mr Oluyede, 56, served as the 56th commander of the elite Infantry Corps of the Nigerian Army, based in Jaji, Kaduna.
Messrs Oluyede and Lagbaja were coursemates and members of the 39th Regular Course of the Nigerian Defence Academy.
He was commissioned as a second lieutenant in 1992, effective from 1987, and rose to major general in September 2020.