Opposition parties from the Democratic Republic of Congo say that they will decide on one joint candidate for December's presidential elections.

After meeting in South Africa, seven parties agreed to name the candidate by the 15 November.

Correspondents say it would be surprising if all the opposition candidates stick to the agreement.

The election should result in DR Congo’s first democratic transition of power.

President Joseph Kabila is due to step down after serving the maximum two terms and the governing party has chosen the former Interior Minister Emmanuel Ramazani Shadary as its candidate.

Mr Kabila was supposed to have relinquished power nearly two years ago when his second term in office ended, but the postponement of elections meant he has stayed on as president.

Two key opposition candidates, Jean Pierre Bemba and Moise Katumbi, were barred from running.

The Congolese authorities have given permission for an opposition demonstration to go ahead in the capital, Kinshasa, on Friday.

The protest is against the use of controversial new voting machines, which some fear will be used to rig the election.