He has missed three straight weekly Cabinet meetings.
Minutes later, the 74-year-old Buhari startled Africa's most populous nation with the news of his departure.
Mr. Buhari stated this Sunday when he hosted the girls in his official residence at Aso Rock Villa, Abuja.
Buhari's spokesman Femi Adesina said: "The president has said that as numerous girls are alive; his administration will strive to get them back".
Adesina said the teenagers had now been "handed over to those who will supervise their rehabilitation".
The source said that the girls were released following negotiations between the extremist group and the Nigerian government.
"They will face a long and hard process to rebuild their lives after the indescribable horror and trauma they have suffered at the hands of Boko Haram", she said.
"And you should know that some of the girls have died of illnesses and some during confrontations; therefore, it is not possible for all of them to return at the end of the day", he added.
Chibok school girls recently freed from Boko Haram captivity are seen in Abuja Nigeria's Sunday, May.
The group representing the families of the girls said they were awaiting confirmation on how many had been released. It is feared that other girls were strapped with explosives and sent on missions as suicide bombers.
Clashes erupt in northwest Syria after de-escalation zones take effect
The Syrian government of President Bashar al-Assad is not a signatory, but its state news agency has said it supports the plan. Russian officials said it will be at least another month until the details are worked out and the safe areas established.
The rehabilitation process has previously been criticised, mainly for keeping the girls in Abuja, around 560 miles from their families in Chibok.
Nigeria announced Saturday night that it did a prisoner swap with Boko Haram to get the fresh batch of 82 girls freed by their captors. Boko Haram has pledged allegiance to the Islamic State, and has increasingly carried out attacks in neighboring countries.
Boko Haram seized a total of 276 girls in the 2014 abduction.
The number of girls hasn't been officially confirmed, however multiple outlets are reporting that they were turned over to the Nigerian military.
Nigeria's government rebuffed criticism by a faction of the former ruling party that it should not have made an exchange for the girls' release, along with other criticism that it waited too long to take such action.
Buhari who received the schools girls who have been missing for three years expressed joy on their freedom and welcomed them back to the society.
The kidnapping was one of the high-profile incidents of Boko Haram's insurgency in Nigeria's northeast, now in its eighth year and with little sign of ending.
A military source said the girls were now in Banki near the Cameroon border for medical checks before being airlifted to Maiduguri, the capital of Borno state.
Although the Nigerian government a year ago claimed to have "crushed" the militant group, its members have continued to carry out attacks. Militants have killed more than 20,000 people, forced over 2.5 million to be displaced and adbucted thousands of women, forcing them into sexual slavery or marriages with its fighters.
Comments