The U.N. deputy secretary-general is warning that Congo is likely to face violence and persistent instability unless political opponents hold talks to resolve an impasse over upcoming elections in the country.

Jan Eliasson told the U.N. Security Council on Thursday that "this tragic, and still preventable, outcome" would reverse Congo's political, security and develop gains in recent years and would require a response "beyond the capacity" of the U.N. peacekeeping mission in the country.

The opposition has expressed concern that the election set for November will be delayed so that President Joseph Kabila will stay in power longer. This is the president's second and final term under constitutional limits.

Eliasson strongly backed international efforts to help arrange a national dialogue with all Congolese parties by the end of July.