Negotiations over the agreement between Kinshasa and Washington lack transparency and breach Congolese law, Corneille Nangaa has claimed

An agreement between the Democratic Republic of the Congo (DR Congo) and the US on critical minerals is "deeply flawed and unconstitutional," the leader of a rebel coalition in the Central African nation has told Reuters.

Corneille Nangaa, who leads the Alliance Fleuve Congo (AFC), which includes the M23 force, said the deal was negotiated behind closed doors and breaches Congolese law.

The strategic partnership, part of the Washington Accord for Peace and Prosperity signed on December 4, is intended to expand US access to critical minerals in return for investment and security cooperation.

However, Nangaa told Reuters on Monday that "the opacity surrounding the negotiations" and "procedural flaws, particularly the violation of the constitution and the law," undermine the agreement's legitimacy.

His comments add to uncertainty over US plans in eastern Congo, where fighting between M23 and state forces has intensified since early last year. The M23 group controls large swaths of mineral-rich territory, including the Rubaya mining area in North Kivu, where much of the country's coltan is produced.

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Nangaa warned that mining concessions promised under the deal could become the subject of disputes, as some sites may already have been allocated to other partners.

"The Americans may have signed it, but they should know they signed it with an illegitimate and corrupt regime," he said during an interview in Goma, the capital of North Kivu, which was seized by M23 in January 2025.

The Congolese presidency has rejected the rebel leader's claims, saying the partnership "fully falls within the constitutional prerogatives" of the government.

It said concerns about conflicting mining contracts were "speculative" and insisted that any cooperation would comply with national mining laws. The government has said it will submit the deal to parliament in March and expects it to be approved.

On Monday, Nangaa said the AFC/M23 coordinates on security matters with neighboring Rwanda and Uganda but denied receiving military support from Kigali.