Negotiators from the Democratic Republic of Congo and the M23 rebel group were in Qatar on Wednesday for talks on a broader truce, a diplomat with knowledge of the talks told AFP.

"Delegations from both the DRC and... M23 are currently in Doha, with the Qataris facilitating the talks," the diplomat told AFP, speaking on condition of anonymity because of the sensitivity of the negotiations.

The M23, said to be backed by Rwanda, had called last week for more talks to address problems left out of a peace agreement between Kigali and Kinshasa inked in Washington in June.

"This round of negotiations will be critical towards reaching an agreement," the diplomat said, adding that Qatari mediators were working closely with the African Union.

Deadly fighting

The deal signed by the DRC and Rwanda was aimed at bringing about an end to fighting that has killed thousands of people in mineral-rich eastern DR Congo.

But the M23, the main armed group fighting Congolese forces, was not present at the Washington talks and called for a separate ceasefire deal with the DRC government.

The M23 seized vast swathes of territory in eastern DRC in a lightning offensive in January and February, including the key provincial capitals of Goma and Bukavu.

Conflict has gripped eastern DRC for more than three decades, driving hundreds of thousands of people from their homes.

Rwanda denies backing M23

Neighbouring Rwanda denies providing military backing to the group, but UN experts say that the Rwandan army has played a "critical" role in the M23 offensive, including engaging in combat.

The front line has stabilised in eastern DRC since February, but fighting still breaks out regularly between the M23 and multiple pro-government militias.