The UN security council imposed an arms embargo on the Congo's M23 and FDLR rebel groups today.
The council took the decision - which needed to be unanimous - the day before Rwanda starts its two-year term on the body.
Both rebel groups are rooted in Rwanda's 1994 genocide where ethnic majority Hutus slaughtered the minority Tutsi population.
The M23 fighters - made up of former Congolese army soldiers - control swathes of eastern Congo.
They are mainly Tutsi and are allegedly backed by Rwanda, though the country denies it.
The FDLR was formed from Hutus who fled to the jungles in the eastern Congo after committing the genocide.
The group has used the area as a base to take back Rwanda.
Congo is widely believed to back the FDLR as a buffer against Rwanda.
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