The presidents of the Democratic Republic of Congo and Rwanda are expected to meet for talks in Luanda this week amid tense relations between the two neighbours.

The talks between Congo’s Felix Tshisekedi and Rwanda’s Paul Kagame are slated for Wednesday in the southern African nation’s coastal capital. Angolan President Joao Lourenco, a leading mediator in the Great Lakes region, will host the tripartite talks.

The summit comes as the vast, mineral-rich DRC struggles to contain dozens of armed groups in the east, many of which are a legacy of two regional wars a quarter century ago.

The flare-up of heavy fighting has revived decades-old animosities between Kinshasa and Kigali, with the DRC blaming Rwanda for a resurgence of a militia called M23.

Rwanda has repeatedly denied backing the rebels, while both countries have accused each other of carrying out cross-border shelling.