It was Kabila's first public statement since Rwanda's President Paul Kagame began warning last week that his country would act against between 8,000 to 10,000 Rwanda Hutu rebels allegedly taking shelter in eastern Congo. Rwanda's warnings have raised fears that the Congo war might be rekindling.
The major central African conflict, officially lasting from 1998 to 2002, drew in the armies of five nations and was responsible for more than three million deaths.
Kagame insists a 5-month-old U.N.-led disarmament program has so far failed to neutralize the Rwandan Hutu rebel forces.
Rwanda has twice invaded eastern Congo, in 1996 and 1998, to hunt down Rwandan Hutu combatants responsible for the 1994 genocide of more than half-a-million minority Tutsis and moderate Hutus.
Rwanda's warnings — followed by U.N. reports this week of suspicious unidentified troop movement in the east — have raised fears of renewed war in central Africa, reviving a 1998-2002 conflict that drew in the armies of five nations and split Africa's third-largest nation.
The United Nation's Office for the Coordination of Humanitarian Affairs reported in a statement Friday that many displaced villagers in the eastern Congo region of Walikale said they were fleeing attacks by the Rwandan army.
Hutu rebels and other groups attacked and looted villages in other areas, the U.N. statement said, adding that thousands of villagers had fled because of clashes and fears of more violence in eastern Congo.
U.N. military observers who flew over eastern Congo on Friday saw two abandoned villages and "visible signs of some villages having been burnt," said M'Hand Ladjouzi, the head of the U.N. mission in Goma, the largest city in eastern Congo. The villages were in an area Congolese officials say the Rwanda army recently attacked.
Observers planned to return to the area Saturday to gather more information.
Congo authorities say Rwanda failed during its own five years in control of east Congo to eliminate the Rwandan Hutu rebels, and accuse Rwanda of seeking ways to maintain its waning influence in Congo's resource-rich east.
"In reality, if today Rwanda has been constrained to reveal to all its bad faith, it is because we are at the point of completely neutralizing the armed groups that have always served as their pretext for attacking our country," Kabila said.
Rwandan "authorities are working to promote insecurity and instability in our country, with the aim of disrupting the transition process and preventing the holding of elections set for next year," the Congo leader charged.
Kabila said Congo's armed forces were on alert.
Rwanda on Friday denied that its forces were behind suspicious troop movements reported by the more than 11,000-member U.N. force in Congo, and again urged forcible disarmament of the last remaining Hutu rebels in the east.
Rwanda demanded that the U.N. mission "be more serious with the threat the group poses to Rwanda," referring to the Rwandan Hutu rebels.
U.N. officials said Thursday that U.N. air and ground patrols have photographed newly occupied encampments and unidentified well-equipped troops in east Congo, bolstering suspicions that Rwanda is making good on its threat to send troops.
International aid agencies said that unrest has sent 1,500 to 2,000 people fleeing from several towns and villages in North Kivu province, just north of the city of Goma and near Congo's border with Rwanda.
The European Union on Friday called on Congo to move quickly toward disarmament of the Rwandan rebels, warned Rwanda against any unilateral action, and urged both countries to solve their problems peaceably.