GOMA, Congo (AP) — A peace agreement between the Congolese government and the M23 rebel group remains uncertain just days before a negotiation deadline expires, Congo's government spokesman said Monday as fighting continued in the country's troubled east.

The rebel group, which is believed to be backed by neighboring Rwanda, overran the eastern city of Goma last November in a humiliating blow to both the Congolese army and the international peacekeepers stationed there, who stood by as the rebels marched in. The columns of fighters retreated weeks later under intense international pressure, warning they would retake the city if Congo failed to meet their demands.

M23 rebels and the government have been hashing out an agreement since December, and were supposed to sign an accord by Friday. All of that has been thrown into doubt following a split in the rebel movement two weeks ago, after a dispute between the commanders of M23.

"Everything needs to be finalized by March 15. That's the president's wish. But we don't know if we will be able to sign by then," government spokesman Lambert Mende told The Associated Press. "We need a counterpart — and it's difficult to identify one at the moment."

The movement's military leader, Gen. Sultani Makenga, dismissed the political head of the movement, Jean-Marie Runiga, in February. Both men then formed their own factions, which have been fighting since. Runiga's faction is said to be allied with Gen. Bosco Ntaganda, who is nicknamed "The Terminator" and is wanted by the International Criminal Court.

On Monday, Makenga's faction attacked Runiga's in an attempt to regain positions lost following the split. Sustained fighting around the area of Rumangabo took place between 9 a.m. and noon, according to fighters on both sides.

"We are at war," said Col. Vianney Kazarama, spokesman for Makenga's faction.

Following the split within the rebel group, the Congolese army retook some of the hills near the Goma airport. Runiga's faction controls Kibumba, which is the next town to the north. Further north is the Rumangabo area and the nearby village of Rugari, which the two sides are now fighting to control. Makenga's base in Rutshuru is beyond that area.

"Since 9 a.m., we've been fighting Bosco's troops in Rugari, but we are now stopping our advance to allow troops who want to defect to our side to join us," said Maj. Fred Ngenzi, who is with Makenga's faction. Because of the fighting, he added: "I think Friday is a bit early to sign an agreement with the Congolese government."

Runiga's faction claims it is the only one entitled to negotiate with the Congolese government since the leader of the M23 delegation for negotiations, François Rucogoza, is still loyal to Runiga. Talks are ongoing in Kampala, the capital of neighboring Uganda.

Runiga's faction also accuses Congo's government of trying to sabotage negotiations by helping Makenga's faction in the fighting.

"We cannot accept this and stand idle. Makenga is a renegade," said Col. Seraphin Mirindi, spokesman for Runiga's faction. "We are in Kampala, but there is an unwillingness from Kinshasa to negotiate. At some point we will have to react."

The M23 rebellion began in April 2012, when hundreds of soldiers defected from the Congolese army. They belonged to a previous rebellion that was integrated in the army following a peace deal signed on March 23, 2009. The rebels claim that the deal was not respected by the Congolese government.

Meanwhile, the United Nation said that a U.N. peacekeeping helicopter with four Russian crew members went missing Saturday between Bukavu and Shabunda, in South Kivu province, and that wreckage had been found.

U.N. spokesman Martin Nesirky said Monday at U.N. headquarters that a rescue team was a few kilometers away from the site, but had not yet been able to reach the wreckage due to rough weather and bad terrain.


AP writer Peter James Spielmann contributed from the United Nations.