The Rwandan government violated U.N. sanctions by playing a pivotal role in the creation of an anti-government mutiny in Congo and supplying the M23 mutineers with weapons, ammunition and young Rwandan recruits, according to a confidential report by United Nations experts.

The report represents the strongest evidence yet that the soldiers, who mutinied in April, had high-level support from the government of Rwandan President Paul Kagame. The standoff with Congolese forces has driven thousands of people from their homes in the eastern part of the country.

The 44-page report concluded that Rwanda violated U.N. Security Council resolutions banning the supply of weapons to armed groups in Congo. The report has been shared with Security Council members but has not been made public. The Washington Post obtained a copy Tuesday.

In anticipation of the report’s release, Rwandan Foreign Minister Louise Mushikiwabo denied Monday that top Rwandan officials backed the mutineers. She insisted that her country’s military leadership had urged the mutineers to put down their arms and resolve their differences with the Congolese army through talks.

“Of course, Rwanda’s top army leadership in no way would be involved in destroying the peace they have been working very hard to build,” she said at a news conference at U.N. headquarters.

The report’s release was delayed for weeks amid allegations by the Congolese government that the United States had sought to block the publication of a document that could prove damaging to Rwanda, a close ally. But the United States and other council members ultimately agreed to provide the report to other members after the experts briefed the Rwandan government on their findings.