The main Hutu rebel group in Burundi, the Forces for the Defence of Democracy (FDD), which has been fighting the Tutsi-led army since 1993, accused Buyoya last Friday of breaking a December truce and said it would suspend its contacts with him.
The army has since accused the FDD of launching attacks on civilians. FDD leader Pierre Nkurunziza denied the accusation, saying his faction was ready to fight but only if provoked by an army attack.
Arriving back in Burundi late on Monday after a trip to Libya and Europe, Buyoya called for fast deployment of ceasefire monitors.
"It is essential to accelerate the mechanisms of monitoring the ceasefire which have been promised by the international community, because...without exterior neutral observation, incidents may happen," he told reporters.
An African Union team of observers has begun deploying in Burundi to monitor the ceasefire. It is due to be followed by a peacekeeping force which will oversee rebel disarmament.
Buyoya dismissed the FDD statement, saying he would wait and see whether the rebels followed through with their threat to suspend talks.
"The statement made by Nkurunziza's FDD is an internal matter for that movement," he said. "We will wait to see if it does not attend the next meeting, then we will know the real intentions of the FDD."
Several Hutu factions are fighting the Tutsi-led government in Burundi, in a war that has killed around 300,000 people since it began almost a decade ago. As well as the FDD, two small rebel groups have also signed up to a peace deal.
But the second main rebel group in Burundi, the Forces for National Liberation, has stayed outside the peace process.
- Reuters - Thomson Reuters Foundation
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