GOMA — Congo's M23 rebels defied a deadline imposed by neighboring nations, saying Tuesday the insurgents will stay in the crucial, eastern city of Goma and will fight the Congolese army if it tries to retake it. Congo's military spokesman Col. Olivier Hamuli called it “a declaration of war” and said the army will resume combat, although he declined to say when. Highlighting the volatility of the situation, a different rebel group based in Congo, known as the FDLR, crossed into neighboring Rwanda and attacked Rwandan army positions, according to villagers, eyewitnesses and Rwanda's military spokesman. It raised the possibility that Congo was directly retaliating against Rwanda, its much-smaller but more affluent neighbor, which has twice gone to war with Congo and which is now believed to be directing the M23 rebellion. Speaking in Goma Tuesday, M23 president Jean-Marie Runiga said the rebels will not leave the city of 1 million which they seized a week ago. The deadline imposed by the International Conference on the Great Lakes Region for the rebels to depart was midnight Monday. At the same time, Runiga said that the rebels would like to negotiate with the Congolese government. In April, when the rebellion began, the group initially said they wanted to revisit the March 23, 2009 peace accord which paved the way for the fighters to join the Congolese military. The group initially claimed that Congo had not held up its end of the bargain, failing to provide the fighters with adequate pay and proper equipment. Congo has already said that they are willing to negotiate with M23 on the basis of the 2009 peace accord, but on Tuesday, Runiga said that they no longer want to talk about only that. “Lots happened between 2009 and 2012. It is better to tackle the root causes of the issue once and for all,” he said. He said that for the armed group to leave Goma, Congo is going to have to agree to a new set of conditions. Runiga addressed reporters in the center of Goma, almost 12 hours after the midnight deadline for their retreat had passed. Female ushers led reporters to their chairs. All of them were wearing Mushanana fabric, a toga-like dress typically worn by Rwandan women. The visual detail emphasized the foreign provenance of the rebels now occupying Goma, who according to the findings of the United Nations Group of Experts are financed by Rwanda, which is providing them with arms, sophisticated communications equipment as well as several battalions of troops. “They have refused to leave the city of Goma. This is a declaration of war, and we intend to resume combat,” said Congo's military spokesman, Hamuli, whose troops have been pushed back to the town of Minova, 60 km outside of Goma. Asked when, he said: “Arrangements are being made by the FARDC (the Congolese military) hierarchy.”— AP