Nigeria aims to secure the release of 200 women and girls abducted by the armed group Boko Haram by Tuesday, a man described as a "senior source at the presidency" has been quoted as saying.
The man, who would not be named, told the Reuters news agency on Saturday that the government was "working hard to meet its own part of the agreement so that the release of the abductees can by effected either on Monday or latest Tuesday".
The head of Nigeria's military, air chief marshal Alex Badeh, announced on Friday that authorities had reached a deal with Boko Haram for a ceasefire.
The truce would enable the release of the women and girls kidnapped while taking exams in a secondary school from the remote northeastern town of Chibok in April.
Officials at the presidency and the military did not immediately respond to a request for comment.
Boko Haram, which conveys messages in videotaped speeches by a man claiming to be its leader, Abubakar Shekau, has also not yet commented on the ceasefire.
Nigeria's military has previously claimed that both Shekau and men posing as him have been killed in operations, but security analysts have disputed this - casting doubt on the identity of the man in the videos.
Some Nigerians are likely to greet claims of a ceasefire with scepticism after five years of violence, especially after suspected Boko Haram fighters were accused of launching a deadly attack on five villages on Saturday.
Since the girls' abduction, Nigeria's military has twice claimed to have rescued some or all of the girls, only to back-track hours later.
Several rounds of negotiations with Boko Haram have been attempted in recent years but they have never achieved a peace deal, partly because the group has several different factions.
The group, whose name translates roughly as "Western education is sinful" has killed thousands of people in its struggle to carve an Islamic state out of religiously mixed Nigeria.