UNITED NATIONS - The U.N. Security Council on Thursday demanded an end to foreign support for the M23 rebels fighting against the Kinshasa government in eastern Democratic Republic of Congo, a rebuke diplomats said was aimed at Rwanda and Uganda.

The 15-nation council issued a statement voicing its "strong condemnation of any and all outside support to the M23 and demand that all support to the M23, including from outside countries, cease immediately."

"They further call upon all countries in the region to cooperate actively with the Congolese authorities in dismantling and demobilizing the M23," the statement said.

It did not name who the foreign supporters were, but envoys said it was clear which countries the council had in mind. Rwanda and Uganda have denied supporting M23 rebels, but council diplomats say privately that those denials - above all Rwanda's - ring hollow.

"These rebels are very well equipped," a diplomat told Reuters. "They're getting help from somewhere."

Earlier this week, U.N. Congo envoy Roger Meece told the council behind closed doors that M23 had gained ground in the east against the Congolese army, which has only limited capabilities to fight the small but capable rebel group, envoys said.