Rebel Gen. Bosco Ntaganda waged mutiny in April after accusing the DRC government of reneging on a 2006 deal that incorporated former militants into the national military. Conflict between rebels, known as M23, and DRC troops has displaced an estimated 100,000 people.
An internal U.N. report reviewed by the BBC in June suggested the Rwandan military is supporting mutineers in DRC, though Rwandan officials described the allegations as baseless.
U.N. Secretary-General Ban Ki-moon issued a statement through his spokesman calling on Rwandan President Paul Kagame and DRC President Joseph Kabila to hold talks to find a way to bring an end to the violence.
Ban, in the statement, called on the leaders to "do everything possible to dissuade the M23 from making further advances and to cease fighting immediately."
Ntaganda is wanted by the International Criminal Court for crimes against humanity. U.N. High Commissioner for Human Rights Navi Pillay has said the human rights record for anti-government forces is "appalling." Many, she said, may be responsible for war crimes.