Rebels in the east of the Democratic Republic of Congo (DRC) face a deadline to lay down their arms, but they have dismissed the ultimatum as irrelevant.
The deadline, set by UN peacekeepers, is 4pm (1400 GMT) on Thursday.
"We consider that this measure does not concern us," Bertrand Bisimwa, the M23 chief, said.
He said his fighters were not in Goma or on the road heading south towards Sake where much fighting has taken place recently.
Goma is the capital of North Kivu province, which borders two of Congo’s eastern neighbours, Rwanda and Uganda.
The UN on Tuesday threatened to use force against rebels near Goma if they did not disarm within 48 hours.
The UN peacekeeping mission, MONUSCO, said it was setting up a security zone around Goma to protect civilians. The security zone operation would not amount to an offensive targeting a specific armed group.
A UN source told Reuters news agency the operation would try to clear up small pockets of rebels who remained near Goma after they were pushed several miles further north during recent clashes.
Rwanda said on Wednesday the decision of the UN had surprised African leaders and risked jeopardising peace talks
"We're worried that such a threat could have easily derailed the peace talks going on in [the Ugandan capital] Kampala," Louise Mushikiwabo, Rwanda's foreign minister, said at a regional summit.
Mushikiwabo, whose country is widely believed to support the M23 rebellion, said leaders at the summit in Nairobi expressed their strong support for negotiations held in Uganda between the DRC and M23 rebels.
M23 rebels captured Goma on November 20 last year, holding it for 10 days.
They left only when leaders from the Great Lakes nations of Central Africa promised fresh negotiations, opening the talks in Kampala.
The M23 rebels are demanding an amnesty and reintegration into the national army, as well as political concessions.
Rwanda denies backing M23.
It has also alleged that commanders of the newly deployed special force with a mandate to neutralise armed groups such as M23 have met with Rwandan Hutu rebels camped in eastern Congo's borderlands.