Regional heads of state began talks Saturday in an effort to find a lasting solution to chronic unrest in the east of the Democratic Republic of Congo but less than a third of those invited turned up.

The mini-summit opened in the Ugandan capital a day late after officials said that regional defence ministers failed to agree on the proposals to be discussed and it was unclear what if anything they had decided.

DR Congo President Joseph Kabila is attending the talks called and hosted by Ugandan counterpart Yoweri Museveni. But Rwandan President Paul Kagame is staying away, represented by his defence and foreign ministers.

Eastern DR Congo has been hit hard by a new rebellion by army defectors who formed a group called the M23, whose members are former fighters in an ethnic Tutsi rebel movement integrated into the military under a 2009 peace deal.

A UN report in June accused Rwanda of backing M23, one of a host of armed groups in the troubled region, causing a surge in tensions between the two neighbours.

Kigali denies the charge, but on Friday Kinshasa's Foreign Minister Raymond Tshibanda said there was still a "war situation" between the two and called for UN sanctions against top Rwandan generals.

"While there has been a lull in military activities by the M23 in North Kivu since July, the situation remains very fragile," the top United Nations' official for central Africa, Abou Moussa, said in a message ahead of the summit.

"I call for the group's immediate and complete cessation of all destabilising activities," he added.

Also attending the meeting, the third in two months, is Tanzanian President Jakaya Kikwete and his counterpart from South Sudan Salva Kiir.

The meeting will consider recommendations drawn up by a panel of regional defence ministers at a meeting in mid-August in the eastern DRC town of Goma.

Leaders of the 11-member International Conference on the Great Lakes Region (ICGLR) have floated the idea of a "neutral" regional force to try to restore peace in eastern DR Congo but it has made little headway.

Analysts say the latest talks are unlikely to achieve more than previous ones.

Even if the summit were to make concrete progress on M23 and relations between Kinshasa and Kigali, a plethora of other armed groups also operate in a region that has been in turmoil for the best part of the past two decades.

Much of the rebel activity consists of abuses against civilians and illegal exploitation of natural resources, be it metals, ivory or timber.

Fighting in the region has displaced more than 220,000 people since April, and more than 57,000 others have fled to Rwanda and Uganda.