Government forces abandoned Goma on Wednesday as the CNDP advanced, leaving about 850 UN peacekeepers between Nkunda's forces and the city.
Goma to Kigali
Bernard Kouchner, the French foreign minister, and David Miliband, his British counterpart, met Kabila for 90 minutes before travelling to Goma.
Later, the two ministers, together with Jendayi Frazer, Washington's senior diplomat for Africa, were due to travel to Kigali to meet Paul Kagame, the president of Rwanda, which has been accused of aiding the CNDP assault.
"We had a good meeting ... The key theme of our discussion has been the need to implement the agreements that have already been made," Miliband after the meeting with Kabil.
"Around the world, people are seeing the makings of a humanitarian crisis and it's vital that politics is used to reverse a further round of deaths and killings."
Referring to the Goma peace accord reached in January this year, Kouchner said: "We do not have to redefine the peace protocol ... That has already been done."
Before leaving for the trip, Kouchner told French Europe 1 radio: "This is a massacre such as Africa has probably never seen, which is taking place virtually before our eyes."
Separately, Mark Malloch-Brown, Britain's Africa minister, said the UK is on standby to provide forces for any EU mission if violence escalates.
But Gordon Brown, the UK prime minister, said a political, rather than a military, solution is needed.
Kabila and Kagame agreed on Friday to attend an emergency summit on the crisis to discuss the crisis, Louis Michel, the the EU development commissioner, said.
Michel said both leaders were clearly sincere about "opting for dialogue and putting an end to the reasons that are undermining the east".
|Nukunda declared a ceasefire as his forces reached the edge of Goma [AFP]
Kigali has repeatedly denied any involvement in the fighting.
"The government of Rwanda is not in this conflict," Louise Muchikiwabo, Rwanda's minister of information, told Al Jazeera.
However, the head of Uruguay's military, which provides 1,300 of the UN peacekeepers operating in DR Congo, said that the CNDP was "backed by tanks, something that general Nkunda had not had until now".
General Jorge Rosales said it was "not easy to identify rebel forces," but suggested that there is a "high probability that troops from Rwanda are operating in the area".
Nkunda has declared a unilateral ceasefire and called direct talks with the government, a demand that Kinshasa has so far ignored.
"If the government can accept the call, we are ready to talk. We support the position of the international community [to stop fighting]. That's why we are in a ceasefire," Nkunda told Al Jazeera in an exclusive interview on Thursday.
Ban Ki-Moon, the UN secretary-general, on Friday urged the leaders in the region to take necessary measures to ensure fighting does not resume.
According to the International Committee of the Red Cross (ICRC), the humanitarian situation in Goma is "catastrophic," with two hospitals having been ransacked by looters on Thursday.
Nkunda's forces have been accused of looting and burning refugee camps in the region, while the UN human rights commissioner said government troops has carried out rapes, killings and lootings around Goma.
Navi Pillay, the UN Human Rights Commissioner, urged the government to take "swift and significant action" to control their troops and protect civilians.
"What happened in Goma should not have happened, as most violations were committed by looting soldiers belonging to the government forces," she said.