"We call on all parties to actualise the ceasefire, and specifically on the M23 to halt further advancement and the armed forces of DRC to cease all retaliatory measures," said Ruto, who is current chair of the East African Community.

"An immediate ceasefire is the only way by which we can create necessary conditions for constructive dialogue and implementation of a comprehensive peace agreement," he added.

The Rwanda-backed M23 armed group has rapidly seized swathes of territory in the mineral-rich eastern DRC in an offensive that has left thousands dead and displaced vast numbers.

Rwandan President Paul Kagame and his Congolese counterpart, Felix Tshisekedi, have both joined the talks in Tanzania, bringing together the eight countries of the East African Community and 16-member South African Development Community.