The US has warned of possible sanctions against Rwandan and Congolese government officials ahead of a summit meant to address the escalating conflict in eastern Congo, according to a diplomatic note seen on Friday.

Kinshasa and Kigali have been blaming each other for renewed turmoil in eastern Congo, where Rwandan-backed M23 rebels have seized the regional capital Goma and are advancing on more territory.

A diplomatic note sent on Friday by Washington to Kenya, which chairs the East African Community and has mediated in the crisis, said stability in the region will require the Rwandan military “to withdraw its forces and advanced weaponry” from Congo.

“As we make these demands of both parties, we will consider sanctions against the non-co-operators, including military and government officials in both governments,” the note said.

The note fell short of naming Rwandan President Paul Kagame, who is accused by the United Nations of backing March 23 Movement (M23) rebels in the Congo’s mineral-rich South Kivu Province. After capturing Goma, the M23 rebels vowed to march to Kinshasa and oust President Felix Tshisekedi from power.

A high-stakes summit of Eastern and Southern African leaders beginning on Friday in Tanzania could bring together Congolese President Tshisekedi and Rwandan President Kagame, who is accused by Congo, the United Nations and other Western partners of arming and supporting the rebels.

Rwanda has consistently denied these allegations.

In July, the US Treasury Department imposed sanctions on the Congo River Alliance, a coalition of rebel groups which includes M23.

That’s the stark warning Jordan’s King Abdullah plans to deliver.

After seizing Goma, the largest city in eastern Congo, last week, M23 on Wednesday took another mining town in a thrust towards the South Kivu provincial capital Bukavu, violating a unilateral ceasefire they had declared.

The UN Office for the Coordination of Humanitarian Affairs estimated on Wednesday that at least 2,800 people had died in the latest onslaught on Goma by the rebels.

UN Human Rights Chief Volker Turk told an emergency meeting of the UN Human Rights Council on Friday that he expected sexual violence in the region, including incidents of rape and sexual slavery, to increase.

• A Tell / Reuters report