Ian Linden, director of the Catholic Institute for International Relations, said that humanitarian officials recently in the region had reported evidence of a military build up in eastern Zaire. Zairean forces, reportedly assisted by foreign mercenaries, have concentrated around the towns of Walikale and Bunia, apparently in preparation for an assault on rebel-held towns.
Zaire's President, Mobutu Sese Soko, returned to Kinshasa this week after cancer treatment in Europe, and appointed a new army chief,General Mahele Bokungo. He pledged to recover territory lost to the Rwandan-backed rebels.
The rebels, backed by Uganda and Rwanda, have seized territory 300 miles long from north to south since October. Zairean troops put up little resistance but are now regrouping.
The rebel leader, Laurent Kabila, urged civilians this week to stay put, but his words failed to stem a stream of people leaving the eastern city of Goma, the biggest of several towns seized by rebels in November.
In a speech on rebel Star Radio, Mr Kabila, president of the Alliance of Democratic Forces for the Liberation of Congo/Zaire, said his forces would defeat any army counterattack launched by Mr Mobutu.
There is little evidence that external powers will permit Zaire to disintegrate in the face of an effort by the rebels to topple Mr Mobutu. The US State Department expressed strong support this week for Zaire remaining a unified state.
Mr Mobutu is now trying to regain his military and political grip on the country. Opposition representatives have urged him to dump Prime Minister Leon Kengo wa Dondo, and set this weekend as the deadline for forming a crisis government.
Amnesty International said yesterday it had received reports from Burundi that up to 500 people were massacred on 3 December in and around a Pentecostal church in Butaganza commune, Kayanza province. The army had reportedly herded villagers into the church, thrown grenades inside and shot those trying to escape. The wounded were bayoneted to death.