Femi Adesina, spokesman for acting President Yemi Osinbajo, said Wednesday that Osinbajo made the announcement during a Federal Executive Council meeting, adding that the unidentified girl is traveling to the capital, Abuja.
The Nigerian government announced on May 6 that 82 Chibok girls, many of them Christians, had been freed by the Islamist militant group.
Aside from the Chibok girls, Boko Haram has kidnapped thousands of other people during its eight-year insurgency, which is aimed at creating an Islamic caliphate in north-eastern Nigeria.
The girl identifies herself as Maida Yakubu, one of 276 schoolgirls kidnapped by Boko Haram in April 2014, reports Al Jazeera. She wonders why "the families who have been longing for them" have had so few opportunities to see them.
Over the weekend, Maida Yakubu, one of the Chibok girls, appeared in a video explaining why she doesn't want to return to her parents.
Of the 270 girls originally kidnapped, around 60 have escaped and more than 100 have been released. When she saw me, she ran and grabbed me and started crying. The last time a group of the girls was released, in October, spelling errors misidentified some of them, which led to parents turning up in Abuja when their daughters were not actually among the freed.
Meanwhile, theatre commander of Operation Lafiya Dole, Major General Lucky Irabor has disclosed that the Boko Haram terrorists have converted internally Displaced Persons camps as recruitment ground for young boys and girls.
Nigeria's government has said the first group of 21 Chibok girls has been receiving medical attention, trauma counseling and rehabilitation. "She looked well kept", he said.
About 2,000 girls and boys have been abducted by Boko Haram since 2014, with many used as sex slaves, fighters and even suicide bombers, according to Amnesty International.
Boko Haram has murdered numerous Christians and attacked several churches.