US Secretary of State Marco Rubio will host the signing of an agreement between Rwanda and the Democratic Republic of Congo following a truce pledge, officials said.

The State Department on its public schedule said that Rubio would sign a "declaration of principles" with DRC Foreign Minister Therese Kayikwamba Wagner and Rwandan Foreign Minister Olivier Nduhungirehe on Friday.

The State Department did not immediately offer further details.

In a surprise announcement Wednesday, the DRC and M23 rebels, who have made rapid advances, said they had agreed to halt fighting in the east of the country while they work toward a permanent truce.

Thousands have been killed in a conflict that has raged along the border of the two countries since January.

UN experts, the United States and other Western governments say that Rwanda supports the M23, which in recent months has seized key cities in the turbulent but resource-rich east of the DRC.

Rwanda denies providing military support to the M23. But after a visit this month, the US envoy—businessman Massad Boulos, who is the father-in-law of President Donald Trump's daughter Tiffany — has called for Rwanda to halt support and withdraw "all Rwandan troops from DRC territory."

Qatar, which has worked with the United States on a range of thorny diplomatic issues, spearheaded talks between Rwanda and the DRC.

The DRC has sought US support in part by offering to reach its own agreement with the United States on access to critical minerals.