The agreement marks a breakthrough in talks and intends to attract billions of dollars of Western investment to a region rich in cobalt, copper, lithium and other minerals.

The official signing of the peace agreement took place earlier Friday at the State Department and was witnessed by Secretary of State Marco Rubio and Senior Adviser for Africa Massad Boulos, whom Trump has largely credited with bringing about the deal.

Rwanda and the Democratic Republic of Congo have signed a peace deal in Washington aimed at ending decades of devastating conflict between the two neighbours, and potentially granting the US lucrative mineral access.