Rwanda has warned it will launch an attack "very soon" on Hutu rebels sheltering in east Congo - an ominous development that raised fears of renewed central African conflict.
UN special representative Mr William Swing "received a call from a Rwandan official informing him there would be an attack very soon ... by the Rwandan army on Congolese territory," said Ms Patricia Tome, a spokeswoman for the UN mission in Congo.
Rwanda has invaded Congo twice in recent years - first in 1996 and again in 1998 - to hunt down Rwandan Hutu rebels, many of whom played a leading role in the 1994 Rwandan genocide, which saw extremists from the Hutu majority orchestrate the slaughter of more than 500,000 people, most of them from the Tutsi minority.
Swing, who is in the eastern city of Bukavu on Congo's eastern border with Rwanda, was in "diplomatic consultations with all parties in the region to avoid any escalation," Ms Tome said.
Rwanda's 1998 invasion of Congo sparked a war that drew in the armies of a half-dozen African nations and left more than three million people dead, mostly civilians who died from famine and disease - indirect effects of the fighting.
The war ended with peace deals in late 2002 that set the stage for Congo's national unity government, which took office in mid-2003.
Sporadic violence has persisted in the country's volatile east, however, most of it blamed on militia groups, Rwandan rebels and Congolese rebels now integrated into the vast country's army.
AP