Large numbers of troops from Rwanda have been pouring across the border into the Democratic Republic of the Congo to help rebels seize the regional capital of Goma before an emergency UN meeting about the crisis takes place on Monday, intelligence officials have warned.

Rwanda Defence Force (RDF) soldiers are believed to have secretly crossed into the eastern DRC over the past few days to assist a lightning offensive by the M23 militia.

Officials speaking to the Observer on condition of anonymity added that the RDF had cranked up the pressure on the embattled Congolese city by amassing vast numbers of troops on the Rwandan side of the border, a few hundred metres from central Goma.