Rwanda and the Democratic Republic of Congo have signed a peace agreement Washington to end fighting that has killed thousands, with the two countries pledging to pull back support for guerrillas — and President Donald Trump boasting of securing mineral wealth.

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.

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.