M23 leaders insist they will attempt to capture the Congolese capital of Kinshasa if Congo's President Joseph Kabila does not negotiate directly with them.
The regional bloc encouraged Congo to "listen, evaluate and resolve the legitimate grievances of M23," according to the statement out of Uganda's capital, Kampala.
Leaders for the rebel movement said they were in Uganda on Saturday, however, Ugandan officials said M23 representatives were not invited to the summit and denied reports that Jean-Marie Runiga, the M23's political leader, was in the country for separate negotiations with the Ugandan government.
"This is a summit for regional leaders, not a negotiation meeting. The rebels cannot be in the summit," said Okello Oryem, Uganda's deputy minister of foreign affairs.
The Rwandan president was also not at the summit, despite reports by the U.N. that the country, along with Uganda, is helping to back the rebel movement. The two countries deny the charges.
In eastern Congo, hundreds of residents in the towns of Sake and Minova walked toward a nearby village on Saturday to avoid more fighting between rebels and the army, who they accuse of looting and rapes.
A resident making the 5-mile walk to Kirotshe said that soldiers from the U.N. peacekeeping group in Congo, known as MONUSCO, told them to leave Sake.
"They told us the army might attack again at Sake," said the resident who spoke on condition of anonymity for fear of her safety. "Soldiers from MONUSCO told us all to go to the hospital."
The U.N. soldiers, however, would not confirm that they had told locals to take refuge in Kirotshe or whether they thought the army would attack.
A surprise attack by the Congolese army on Thursday afternoon pushed the M23 rebels out of Sake for a few hours. By the evening, however, M23 fighters had recovered the town and forced the government troops to flee 15 miles south to Minova, on the shore of Lake Kivu.
Locals in Minova on Saturday reported that the retreating army troops had gone on a rampage on Thursday and Friday nights.
"Things are not at all well here," said Mousinganga Siprian, an elderly resident of Minova leaning unsteadily on a makeshift crutch. "There are very many soldiers here now. They have looted, they have killed, they are raping our women."
A U.N. source in Minova confirmed that the government soldiers had looted and raped on both of the nights they had spent in the town since their retreat from Sake, but spoke on condition of anonymity because he was not permitted to speak to the press.
The soldiers milled in the streets of Minova, drinking black banana beer and standing on grassy banks or walking among the local population. Many were drunk and aggressive, and the atmosphere between fighters and civilians was extremely tense.
The army commander, Gen. Lucien Bahuma, would not comment on the behavior of his troops when contacted by telephone.
Sake residents settled in for their third evening away from their homes on a road running into Goma.
A World Food Program distribution was taking place, but the displaced people on the roadside said they were unsatisfied with the support they were getting.
"They are giving out food but only bit by bit," said Jacqui Nadaje, clutching a bright orange washing bowl full of clothes. "This is the first time (the WFP) has come here. We need more support from these agencies and the international community. We need shelter and water, but above all we need food. We are all very hungry."
The regional leaders in Uganda's capital said The U.N. peacekeeping mission in Congo, or MONUSCO, is to occupy and provide security in the "neutral zone between Goma and the new areas occupied by M23." It also called for the creation of a "composite force" to guard Goma's strategic airport that would feature soldiers from other African countries as well as M23 and the Congolese national army. Regional governments are considering dispatching a "natural international force" to eastern Congo, but it remains unclear when it would materialize.
South Africa offered Saturday to contribute some money toward the force, but only Tanzania has offered troops so far. Angola and Kenya, which are eligible to contribute troops, have not announced their offers.