Leaders from Africa's Great Lakes regional nations have signed a new peace deal aimed at bringing stability to the war-torn east of the Democratic Republic of the Congo (DRC).

Ban Ki-moon, the UN secretary-general, witnessed the signing on Sunday at the African Union's headquarters in Addis Ababa, Ethiopia.

The presidents of the DRC, Angola, Burundi, Central African Republic, Republic of Congo, Rwanda, South Africa, South Sudan, Tanzania, Uganda and Zambia either attended or delegated the power to sign the deal.

According to the UN, the "peace framework agreement" could lead to the creation of a special UN intervention brigade in eastern DRC to combat rebel groups and renew political efforts.

But after almost two decades of war, expectations are low.

"I think it would be wrong to have too great expectations because the situation here is very difficult," Alex Queval, head of the UN mission in North Kivu, told Al Jazeera. "The conflict has been going on for at least 19 years, so it's not going to be solved overnight, but I definitely think that this approach can be a new beginning."

Al Jazeera's Nazanine Moshiri, reporting from the Mugunga camp for internally displaced persons outside Goma, said people there "really hope this [agreement] is the beginning of something."

Mugunga is host to tens of thousands of Congolese people who had to flee their homes following violence in the east in November 2012.

Despite the signing on Sunday, problems remain with the peace process, she said.

"We still dont know what kind of powers a special UN envoy would have [and] whether those signing will have a mechanism overseeing whether they will abide by what they signed up for," she said.

Rebel movements

The DRC's mineral-rich east has been ravaged by numerous armed groups, with new rebel movements spawned on a regular basis, some of them with backing from neighbouring countries.

The latest surge in violence was in 2012 and culminated in the rebel March 23 Movement (M23) force briefly seizing the key town of Goma last November.

M23, which was not invited to Sunday's meeting, was founded by former fighters of an ethnic-Tutsi rebel group whose members were integrated into the regular army under a peace deal whose terms they claim were never fully delivered.

The group's main demand now is the full implementation of a peace accord signed on March 23, 2009.

M23 controls part of the Rutshuru region, an unstable but fertile territory that lies in mineral-rich North Kivu province and borders on Rwanda and Uganda.

Several of its leaders have been hit by UN sanctions over alleged atrocities. The group has been accused of raping women and girls, using child soldiers and killing civilians.

Failed attempts

Peace talks have been held in Uganda, but so far have made little headway.

MONUSCO, the peacekeeping mission already deployed in DRC, is one of the UN's biggest.

It currently has about 17,000 troops and, under its Security Council mandate, is allowed to have up to 19,800.

The UN wants to toughen MONUSCO with the addition of a 2,500-strong intervention brigade to tackle the armed groups that have plagued the resource-rich region.

A first attempt to sign the agreement last month was called off over procedural concerns, not over the content of the agreement, the UN said.

Moshiri said civil society groups have complained that "they're not involved in Sunday's agreement, and that there is no concrete action plan to deal with the root causes of the conflict, which are mainly poverty and corruption".