European Union Development and Humanitarian Aid Commissioner Louis Michel says the presidents of both countries will attend an emergency summit sponsored by the United Nations and the African Union.
Rebels led by General Laurent Nkunda declared a cease-fire Wednesday, but not before advancing to within 15 kilometers of the eastern Congolese city of Goma.
The U.N. refugee agency says almost 4,000 people have fled to Rwanda and Uganda in recent days. Agency spokesman Ron Redmond says without more resources, conditions could soon deteriorate.
Meanwhile, French Foreign Minister Bernard Kouchner and his British counterpart, David Miliband, moved ahead with crisis talks, meeting Saturday with Congolese President Joseph Kabila in Kinshasa. They also will travel to Rwanda for talks with President Paul Kagame.
Officials from the U.N. and the AU have been calling for a regional summit in an effort to end the crisis.
Congolese troops and rebel forces began a series of clashes in late August after the collapse of a January peace deal.
The rebels say they are defending ethnic Tutsis in the region against Rwandan Hutu fighters, who crossed into Congo after Rwanda's 1994 genocide.
Congolese authorities have accused the Rwandan government of backing Nkunda, and the two countries have accused each other's troops of crossing the border and firing at each other in the recent clashes.
Meanwhile, U.N. Human Rights Commissioner Navi Pillay has condemned Congolese government troops for a spree of looting, raping and killing in Goma on Wednesday. The U.N. said Friday that 21 people were killed, including eight government soldiers shot while engaging in looting.
Some information for this report was provided by AFP, AP and Reuters.