The United States offered to extend its signature African investment project into the troubled east of the Democratic Republic of Congo as an incentive for a peace deal, but Rwanda has backed away, a senior US diplomat said.

Molly Phee, the outgoing assistant secretary of state for African affairs, said the United States proposed an expansion of the Lobito railway, a project visited last month by President Joe Biden that aims to speed up the transport of minerals from southern DRC and Zambia to Angola’s Atlantic coast.

“We had proposed to both sides that if we could get to stabilization in eastern DRC, we could work on developing a spur from the Lobito Corridor up through eastern DRC,” Phee told AFP in an interview ahead of her exit Monday as the Biden administration comes to an end.

“We tried to offer positive incentives. A genuine framework – fundamentally negotiated by the parties – exists, and at the moment, Rwanda seems to have walked away,” she said.

Phee, who was part of the Biden administration’s negotiations along with US intelligence chief Avril Haines, said the United States presented a solution that would include a DRC crackdown on the FDLR.

“They did not take that action,” she said of Kinshasa.

“We put it all back together again and then I thought we were on a good track. And then in the end, President Kagame decided not to go to the Luanda summit in December, and you’ve seen Rwanda and M23 take more territory.”

Kagame has dismissed recent peace initiatives such as the summit in the Angolan capital Luanda as little more than photo-ops that do not address “root causes.”