"The girls, we believe, are alive but they have been moved from the location to which they were originally taken," the intermediary told Channel 4 News. "It would not be hard to engineer a deal. It looks like they want to release them."
The kidnappers have warned, however, that attempts by the military to launch a rescue attempt "may result in the deaths of many of the captives".
"They want a way out," said the negotiator, who has long experience of dealing directly with the Islamist group Boko Haram in previous hostage crises.
