The Rwanda-backed rebels who captured key areas of Congo’s mineral-rich east say they have withdrawn from planned peace talks with the country’s government in Angola.

Rwanda-backed M23 rebels on Monday pulled out of peace talks with the Democratic Republic of Congo's government less than 24 hours before the warring parties in eastern Congo's worst conflict in decades were due to convene in Angola.

Angola has acted as a mediator in the conflict in eastern Congo , which escalated in late January when the Rwanda-backed rebels advanced and took control of the strategic eastern Congo city of Goma. M23 seized Bukavu, eastern Congo’s second biggest city, last month.

The presidents of Congo and neighboring Rwanda met Tuesday in Qatar for their first direct talks since Rwanda-backed M23 rebels seized two major cities in mineral-rich eastern Congo earlier this year.

Democratic Republic of Congo's President Felix Tshisekedi has met U.S. lawmaker Ronny Jackson to discuss fighting in the east of the country and opportunities for U.S. investment, Congo's presidency said.

Democratic Republic of Congo President Felix Tshisekedi and his Rwandan counterpart Paul Kagame called for a ceasefire in eastern Congo on Tuesday during their first meeting since M23 rebels stepped up an offensive there in January.