Addis Ababa - The African Union on Wednesday threatened to sanction Burundi's rival factions if they failed to attend peace talks next month, as it pushes the government to accept a peacekeeping force.
Burundi's government and opposition, who met in Uganda on Monday, are due to meet again in January in the northern Tanzanian town of Arusha for talks aimed at ending months of violence.
The unrest has raised fear of a return to all-out war in the tiny central African nation, nine years after the end of a civil war.
Ugandan officials said talks would resume on January 6 but the Burundi government delegation said "no consensus" had been reached on the date.
AU Commission chief Nkosazana Dlamini-Zuma warned of sanctions if violence continues and talks do not go ahead.
"All those whose action could jeopardize the inter-Burundian dialogue, including attacks by armed groups against governmental facilities and other targets, as well as refusal to respond to the invitation of the mediator, shall be subjected to sanctions," AU Commission chief Nkosazana Dlamini-Zuma said in a statement seen on Wednesday.
She gave no further details of possible sanctions, which have been threatened before, but called for "unreserved cooperation" with the peace process "in order to put an end to the violence."
The unrest began in April when President Pierre Nkurunziza announced his intention to run for a controversial third term, which he went on to win in July.
The 54-member African Union gave Burundi a four-day deadline on December 17 to accept a 5,000-strong force to halt the violence, pledging to send troops despite Burundi saying it was opposed to an "invasion force."
The force, the African Prevention and Protection Mission in Burundi, is known by its acronym in French, MAPROBU.
The AU is "ready to engage, without any delay" negotiations with Bujumbura to push the deployment of the force, Dlamini-Zuma said.
"The rapid deployment of MAPROBU will go a long way in contributing to the creation of conditions conducive to the successful completion of the inter-Burundian dialogue," she added.
Burundi is still recovering from an ethnically-charged civil war between majority Hutus and minority Tutsis, which cost an estimated 300 000 lives between 1993 and 2006.