Rwanda is among five nations elected to the UN Security Council, amid an ongoing investigation by a UN panel of its role in neighbouring Congo's rebellion.
An unpublished UN experts' report, leaked to the media this week, accuses Rwanda and Uganda of actively supporting the M23 rebels in eastern Congo. Rwanda and Uganda deny the charges.
The M23's rebellion has caused more than 200,000 villagers in the province of North Kivu to flee their homes this year. Eastern Congo has been engulfed in fighting since the 1994 Rwanda genocide.
Rwanda won a two-year non-permanent seat on the council, starting in 2013.
Other nations joining the Security Council in 2013 include Argentina, Australia, Luxembourg and South Korea. Each gained the required two-thirds majority in the General Assembly.