The claim is believed to have been made by the Boko Haram leader, Abubakar Shekau, in a new video, Nigerian newspaper Premium Times reported.
The girls were kidnapped from the dormitory of Government Secondary School, Chibok, on the night of April 14.
President Goodluck Jonathan Sunday had dismissed news that the government was negotiating with the insurgents to secure the release of the abducted schoolgirls in Chibok town of the northeastern state of Borno.
"The government cannot negotiate with faceless people," said Jonathan, while reassuring parents, guardians and all Nigerians that government would rescue all the abducted girls.
The actual number of girls kidnapped is yet to be verified but sources say over 200 girls have been reported missing.