Adesina also debunked reports saying that Buhari asked Vice President Osinbajo to continue to act on his behalf.
He said that the letter would formalise the president’s return.
He said: “PMB (President Muhammadu Buhari) will on Monday transmit letter to National Assembly on his return to the country. That makes his return to work formal and constitutional.’’
Adesina’s post debunks some reports indicating that the President has asked Vice President Yemi Osinbajo to continue to act on his behalf.
The News Agency of Nigeria (NAN) reports that the president left the country on Jan. 19 to begin a 10 day leave.
He informed the National Assembly and transferred power to his deputy, Professor Yemi Osinbajo.
The president later wrote the National Assembly for an extension of the leave to enable him to undergo more medical tests based on the advice of his doctors.
President Buhari, however, returned to Nigeria on Friday after more than six-weeks in the United Kingdom.
The president arrived in the country through Kaduna Airport following Wednesday’s closure of Nnamdi Azikiwe International Airport, Abuja, for rehabilitation.
The Presidential plane landed at the VIP Wing of the 401 Flying Training School of the Nigerian Air Force, Kaduna, at about 7.40 a.m.
He was received by the Deputy Governor of Kaduna State, Mr Barnabas Yusuf Bala.
The president was later flown by a helicopter to Abuja.