In a unanimous vote, the Security Council extended the term for the five judges serving on the U.N.-backed International Criminal Tribunal for Rwanda.
The ICTR, working from neighboring Tanzania, has acquitted eight and convicted 38 people who faced charges related to genocide. Some cases were referred to Rwandan courts.
The Security Council said the judges' tenure extend to Dec. 31, 2014, "or until the completion of the cases to which they are assigned."
Conflicts between the Hutu and Tutsi ethnic communities left about 800,000 people dead in a 100-day massacre in 1994.
U.N. peacekeepers in Democratic Republic of Congo escorted national police to Goma, the capital of North Kivu province, after forces from the March 23 movement pulled back this month.
M23 is comprised of Tutsi rebels and is suspected of committing crimes during its rebellion. It allegedly has the support of the Rwanda government, an allegation Kigali denies.
The British government in November said it was withholding $33.6 million in aid to Rwanda because of concerns about rebel support in eastern DRC.