UNITED NATIONS (AP) — The U.N. Security Council on Monday imposed an arms embargo on the M23 and FDLR rebel groups in an attempt to quell fighting in Congo's conflict-wracked eastern region.

The council committee monitoring sanctions against Congo also imposed a travel ban and financial freeze on the assets of two M23 leaders —the rebel group's president Jean-Marie Runiga and one of its military commanders, Lt. Col. Eric Badege.

The council acted on New Year's Eve, a day before Rwanda joins the U.N.'s most powerful body for a two-year term. The sanctions needed approval by all 15 council members.

U.S. Ambassador Susan Rice welcomed the unanimous agreement saying the United States believes the new sanctions "will directly help advance the goal of a sustainable peace" in eastern Congo.

"We urge the rank and file of both the M23 and the FDLR to defect and demobilize in order to disassociate themselves from the sanctioned groups," Rice said in a statement.

Both rebel groups have their origins in the scars left by Rwanda's 1994 genocide.

The M23 are fighters mainly from the Tutsi ethnic group that was targeted for extermination during the genocide and are believed to be backed by Rwanda. The Rwandan government denies any support.

Made up of hundreds of soldiers who deserted the Congolese army in April, the M23 rebels have taken control of many villages and towns in the mineral-rich east since then and briefly held the key eastern city of Goma before withdrawing several weeks ago. They have since taken steps toward negotiating with the Congolese government but residents in Goma said about 10 days ago that the M23 and other armed fighters were positioning themselves in an around the city.

The perpetrators of the 1994 Rwanda genocide were from the Hutu ethnic group who fled across the border and took refuge in the jungles of eastern Congo. Their leaders regrouped under the banner of the Democratic Forces for the Liberation of Rwanda, or FDLR.

Hutu extremist fighters from the FDLR have used Congo as a base to try to take back Rwanda. Numerous reports indicate that the FDLR is tacitly backed by Congo, which wanted to use them as a buffer against Rwanda.

Rice said the international community remains deeply concerned about the rapidly deteriorating security and humanitarian crisis in eastern Congo due to ongoing military activities of the M23.

She called the sanctions against the FLDR "a critical step toward ending impunity and advancing peace," noting that for years the FDLR has committed atrocities against civilians.