In his first public remarks since the M23 rebels advanced into eastern Congo’s largest city, Goma, on Monday, President Tshisekedi late on Wednesday vowed “a vigorous and co-ordinated response” to push back the rebels while reaffirming his commitment to a peaceful resolution.

There are growing international calls for peace talks to end the escalation of violence in the east of the Democratic Republic of Congo. The fate of the economic and trading hub Goma is still unclear. UN officials have said the situation is chaotic with fighting continuing in parts of the city.

"Active zones of combat have spread to all quarters of the city, all the neighborhoods of the city," Lemarquis, the deputy U.N. envoy and top U.N. aid official in the DRC, told reporters in New York via video from Kinshasa.

Thousands of residents who fled following a major escalation of the decades-long conflict arrived at the Rwandan border, as M23 rebels consolidate control of the city of Goma. View on euronews

A rebel alliance spearheaded by the ethnic Tutsi-led M23 militia said it had seized the lakeside city of more than 2 million people.

Rebels appear to be edging closer to taking control of the key city of Goma in the east of the Democratic Republic of Congo following reports that they had captured its airport. The Congolese government has insisted that it is still in charge as fighting in parts of the city continues.

Rwanda-backed fighters controlled most of the besieged DR Congo city of Goma on Wednesday as residents slowly emerged from their homes after days of deadly fighting in the key mineral

Rwanda-backed fighters advanced on a second front in their lightning offensive across eastern DR Congo on Wednesday after seizing control of most of the key city of Goma during heavy fighting with the Congolese military.