Democratic Republic of Congo and the M23 rebel group pledged to sign a peace agreement by August 18, at a ceremony in Doha on Saturday, a sign of progress even as outstanding details need to be negotiated.

Thousands were killed in a lightning offensive by the M23 in January and February, in which the group seized vast swathes of territory in the DRC, including the key eastern provincial capitals of Goma and Bukavu.

The Democratic Republic of Congo and M23 rebels have signed a ceasefire deal in Qatar to end fighting between the warring sides. Dubbed the Declaration of Principles, Saturday's agreement seen by the BBC, says both sides must refrain from attacks, "hate propaganda" and "any attempt to seize by force new positions on the ground".