North Kivu province has been battling the M23 insurgency for more than two years as well as other militia violence.
DRC, the United Nations (UN) and Western powers have repeatedly accused Rwanda of supporting M23 with its own troops and weapons, which it denies.
Rwanda accuses DRC of financing and fighting alongside a Hutu rebel group, the Democratic Forces for the Liberation of Rwanda (FDLR), which has attacked Tutsis in both countries.
M23 says it is fighting to protect Tutsis from rivals like FDLR, whose ranks include Hutu extremists who fled to DRC after participating in the 1994 genocide targeting Tutsis and moderate Hutus in Rwanda.
"We commit to working with the Governments of the DRC, Rwanda, and Angola to use this truce extension to outline a series of steps to reach a durable cessation of hostilities," White House National Security Council Spokesperson Adrienne Watson said in a statement.
--Reuters--