Nigeria says it is still holding talks with Boko Haram, two weeks after the government said it had agreed a truce with the Islamist militant group.
A presidential spokesman said he was optimistic that something “concrete and positive” would come out of the talks.
There has been no comment from Boko Haram, and violence in northern Nigeria has continued.
More than 200 schoolgirls are still being held by the group, which has been fighting an insurgency since 2009.
The military had said they were expecting their release by Friday, but only two of the girls have been freed, and the circumstances surrounding their release are unclear.
Boko Haram has killed at least 2,000 civilians this year.
‘Optimistic’
Boko Haram sparked global outrage six months ago when they abducted the schoolgirls from the north-eastern town of Chibok in Borno state.
The girls’ continued captivity has led to criticism of the Nigerian government’s efforts to secure their release.
Nigerian presidential spokesman Reuben Abati told the BBC that that the governments of Cameroon and Chad were also involved with the negotiations.