(Adds detail in paragraph 16)
By Michelle Nichols and Louis Charbonneau
UNITED NATIONS, Jan 30 (Reuters) - The U.N. Security Council stressed on Thursday that M23 rebels must be stopped from regrouping in Democratic Republic of Congo and expressed concern at Congolese soldiers aiding Rwandan Hutu militia, sparking a verbal clash between the countries' envoys.
Rwanda's U.N. ambassador, Eugene Gasana - a temporary member of the 15-member Security Council - accused Congo of "crying like small babies," while his Congolese counterpart, Ignace Gata Mavita wa Lufuta, said Rwanda's "arrogant behavior must stop."
Rwanda has repeatedly intervened in Congo, saying it had to hunt down Hutu militia, the Democratic Forces for the Liberation of Rwanda (FDLR), which fled after Rwanda's 1994 genocide. Congo and Rwanda have fought two wars in two decades in eastern Congo.
The U.N. Security Council expressed its concerns about the violence in eastern Congo in a unanimously adopted resolution that renewed an arms embargo and targeted sanctions, including travel bans and asset freezes, on Democratic Republic of Congo.
The top U.N. official in Congo, Martin Kobler, has said there were credible reports that the M23 rebels appeared to be regrouping just two months after Congolese troops and U.N. peacekeepers defeated the Tutsi-led insurgency.
U.N. experts, who monitor violations of U.N. sanctions on Congo, and Democratic Republic of Congo have long accused Rwanda of backing M23, which ended its 20-month rebellion in November, a claim that Kigali has fiercely rejected.
Rwanda and the U.N. experts have accused Congolese troops of collaborating with the FDLR, which includes Hutus who fled Rwanda after the genocide of 800,000 Tutsi and moderate Hutus. Kinshasa denies the claim.
"These guys (Congo), just every other day, coming and crying like small babies," Gasana told reporters after the council meeting. "Rwanda, it's a small country. Congo is rich. Congo has everything. How come Rwanda is always the scapegoat?"
Gata Mavita wa Lufuta told the Security Council: "We are a sovereign country and we must be respected as such and this arrogant behavior (by Rwanda) must stop."
REPORTS OF CONGOLESE ARMY COLLABORATION
There was one thing both ambassadors agreed on: the U.N. Security Council was not the appropriate venue for their verbal spat.
Millions of people have died from violence, disease and hunger in Congo since the 1990s as armed groups have fought for control of the country's vast deposits of gold, diamonds, copper, cobalt and uranium.
The Security Council resolution noted "with deep concern reports indicating FARDC (Congolese army) collaboration with the FDLR at a local level, recalling that the FDLR is a group under U.N. sanctions whose leaders and members include perpetrators of the 1994 genocide."
It stressed the importance of "permanently addressing this threat."
A 20,000-strong U.N. peacekeeping force in Congo received a boost last year with the unprecedented deployments of unarmed surveillance drones and an Intervention Brigade of 3,000 troops to help Congolese forces hunt down rebel groups.
After the military defeat of M23, the peacekeepers and the Congolese army have turned their attention to tackling the FDLR and the Allied Democratic Forces, a Ugandan Islamist group.
The resolution asked the United Nations and international organizations to work with neighboring states to "urgently address the situation of former M23 combatants located in their territories, and stresses the importance of ensuring that the M23 does not regroup and resume military activities."
It also called upon countries in the region to take steps to ensure there is no support in or from their territories for armed groups in eastern Congo. U.N. experts have also accused Uganda of aiding Congolese rebels, which Kampala has denied. (Reporting by Michelle Nichols; Editing by Leslie Adler and Lisa Shumaker)