Uganda's Lord's Resistance Army (LRA) rebel group has pulled out of peace talks, demanding the government declare a ceasefire as the LRA has done.
An LRA spokesman told the BBC the government's refusal to do so showed it was not serious about the talks.
But the government says it wants a ceasefire to be part of a comprehensive settlement as the LRA has used previous ceasefire declarations to rearm.
It says its team is in discussions with the mediators to find a way forward.
The talks brokered by the government of south Sudan are considered to be the best chance of ending the two-decade conflict in northern Uganda.
'Against the spirit of the talks'
LRA spokesman Obonyo Olweny said that during the recent recess in talks, the rebels had been told by mediators that a unilateral ceasefire was a precondition for the resumption of negotiations.
Who are the LRA rebels?
As a consequence, the rebels had declared a unilateral ceasefire, starting last Friday.
"Therefore we think it is inappropriate for the talks to resume without the government of Uganda declaring a cessation of hostilities," he told the BBC's Focus on Africa programme.
Mr Olweny said the government had recently killed eight of its fighters, which was against the "spirit of the peace talks".
But Ugandan government spokesman Robert Kabushenga said the government was unsure of the rebels' commitment to peace, as they had breached previous ceasefires and harmed innocent people.
"The point is very simple, we have said that if you are committed, then do it on paper because then it is verifiable. Sign that you are committed to a comprehensive peace agreement," he told the BBC.
The LRA's deputy leader Vincent Otti announced the ceasefire last week.
"I do hope that the government of Uganda shall reciprocate this gesture of goodwill so that the warring parties may finally find a bilateral agreement to provide a peaceful atmosphere for our people," he said.
The southern Sudanese vice-president and head mediator, Riek Machar, had asked for the group's top leaders to take part after earlier peace talks failed.
But Mr Otti said that the southern Sudanese town of Juba was not safe because an International Criminal Court (ICC) warrant for the LRA leaders' arrest was still in force and Ugandan government forces were present in the town.
Ugandan President Yoweri Museveni has offered the rebels a full and guaranteed amnesty and protection as long as they renounce violence.
Tens of thousands have been killed in the conflict and two million people have been displaced.
^ Back to top | BBC Sport Home | BBC Homepage | Contact us | Help | ©