The mineral-rich DRC is struggling to contain dozens of armed groups in the east of the vast nation, many of which are a legacy of two regional wars a quarter of a century ago.

Weeks of violence have grown into a diplomatic standoff between the DRC and its neighbour Rwanda, who it blames for the recent resurgence of the M23 rebel militia.

Rwanda has repeatedly denied backing the rebels while both countries have accused each other of carrying out cross-border shelling.

"I call for the activation of the East African Regional Force under the auspices of the East African Community (EAC)," Kenyatta said in a statement.

The "open hostilities" threatened to derail an ongoing political process to address the security situation in the country of 90 million people, he added.

The decision to establish a regional force was arrived at in April when Kenyatta hosted the leaders of Uganda, Burundi, Rwanda and the DRC in Nairobi to discuss the crisis.

Regional commanders of the seven-nation EAC bloc will meet on Sunday to finalise preparations for the deployment of the joint force, Kenyatta said.

"The East African Regional Force shall be deployed to the Ituri, North Kivu and South Kivu provinces immediately to stabilise the zone and enforce peace."

A UN force, known by its French acronym MONUSCO, is already operating in the DRC.

Kenyatta said the regional force will work alongside local provincial authorities and in close coordination with MONUSCO to disarm anyone bearing illegal firearms.

His comments followed discussions between East African army chiefs in eastern DRC's commercial hub Goma last week on the "initial modalities" of establishing a regional military force.

- Volatile region -

The volatile area is also a geopolitical cauldron, sharing borders with Uganda, Rwanda and Burundi, among others.

Uganda has committed troops to fight the notorious Allied Democratic Forces in eastern DRC, on the Congolese government's invitation.

But tensions between Rwanda and the DRC have surged following a comeback by the M23 militia, which this week claimed control of the key border town of Bunagana, forcing thousands to flee their homes.

A primarily Congolese Tutsi militia that is one of scores of armed groups in eastern DRC, the M23 leapt to global prominence in 2012 when it captured Goma.

It was forced out shortly afterwards in a joint offensive by UN troops and the Congolese army.

The group took up arms again in late November having accused the Kinshasa government of failing to respect a 2009 agreement that involved incorporating its fighters into the army.

Relations between Kinshasa and Kigali have been strained since the mass arrival in the DRC of Rwandan Hutus accused of slaughtering Tutsis during the 1994 Rwanda genocide.