'A U.N. Security Council sanctions committee on Monday blacklisted two rebel groups that have been responsible for war crimes in conflict-ravaged eastern Democratic Republic of the Congo, the United Nations said in a statement.

The United States and Britain praised the move, with Washington suggesting further sanctions may be imposed against anyone who continues to cause trouble in eastern Congo.

One of the groups added to the blacklist is the so-called M23, a Congolese rebel faction led by Bosco Ntaganda, a warlord indicted by the International Criminal Court.

M23 initially said they took up arms over what they called Kinshasa's failure to keep a 2009 peace deal that saw them integrated into the army. They later broadened the scope of their movement, making its goal the "liberation" of all of Congo and the ouster of President Joseph Kabila.

The U.N. statement said M23, which is widely believed to be receiving support from neighboring Rwanda, has been complicit in serious crimes such as "killing and maiming, sexual violence, abduction, and forced displacement."

No Rwandans have been sanctioned in connection with M23, which diplomats have said on condition of anonymity was because the United States, in particular, opposes any such moves as counterproductive.

The other rebel organization hit with sanctions on Monday is the FDLR, or Democratic Forces for the Liberation of Rwanda. The FDLR is a Rwandan Hutu group that opposes President Paul Kagame's Tutsi-led government in Kigali and includes Hutu militiamen suspected of participating in Rwanda's 1994 genocide.

FDLR has been guilty of "targeting of women and children in armed conflict in the DRC, including killing and maiming, sexual violence, and forced displacement," the U.N. statement said.