UN experts and the DRC government accuse neighbouring Rwanda of backing the M23 rebels who launched an uprising in April.
"Congress, in your hands you have the salvation of all Congolese people," Ntambo Nkulu Ntanda, bishop of the United Methodist Church of North Katanga, told a house of representatives subcommittee.
"We came to seek your assistance because we know who you are. You have power … you have all the means to stop the war in Congo."
Vividly etching shocking images of daily brutality against women and children, he said: "More than six million have been killed, and they're still being killed."
But he accused the world of turning a blind eye saying "no-one is paying attention, even having compassion to us".
UN experts and the DRC government accuse neighbouring Rwanda of backing the M23 rebels who launched an uprising in April. Rwanda has denied any involvement and in turn accuses Kinshasa of backing a group of Hutu rebels who also operate in eastern DRC.
New conflict
The M23 is led by Bosco Ntaganda, wanted by the International Criminal Court (ICC) for war crimes, and is formed by former fighters in an ethnic Tutsi rebel group integrated into the Congolese military in a 2009 peace deal.
Nearly half a million civilians have been displaced by the new conflict, and there is growing pressure for progress to be made at a UN summit on the crisis to be held in New York on September 27.
Expert Mark Schneider, senior vice president of the International Crisis Group, which studies conflict-torn states, said the US could take a lead on bringing together humanitarian efforts to help the displaced.
Global powers should also insist on an immediate ceasefire monitored by the UN peacekeeping force in the region, along with tougher sanctions targeting any people including Rwandan leaders found to be supporting the rebels.
The ICC should also be asked to investigate the rapes and killings, and the M23 leader arrested and handed over for trial.
Crisis management
"If the Western nations, including the US, want to move from crisis management, to conflict resolution in the Great Lakes region, they have to speak with a single clear voice and exert direct political pressure on both Kinshasa and Kigali," Schneider said.
Jason Stearns, Director of the Usalama Project at Rift Valley Institute, said the crisis and rise of the M23 resulted from "the failure of the Congolese peace process to deal with persistent causes of conflict in the region."
He urged the United States to deepen its engagement saying the region had only a low priority with the administration. But he stressed no solution could be imposed by outsiders, saying a high-level African-led option would have the best chance of success.
"The key problem the US government has had is apathy. It's not that it's done the wrong things. It's that they haven't done anything at all," he added. – Sapa-AFP