US Secretary of State Antony Blinken called Rwanda's leader on Tuesday and pressed for a de-escalation after a new flare-up in tensions with the Democratic Republic of Congo.
Kinshasa's military late last month accused Rwandan forces of entering its troubled border area, a claim denied by Kigali, which has also been accused of backing rebels in Eastern DR Congo.
The State Department said Blinken had a "productive" call with Rwandan President Paul Kagame about the "volatile situation", without taking a stance on the alleged border incursion.
The call comes after Blinken's deputy, Victoria Nuland, visited Kinshasa and discussed the friction with Rwanda with President Felix Tshisekedi.
"Blinken relayed US advocacy for a diplomatic solution to the tensions between the two countries and (its) request for each side to take measures to de-escalate the situation," a State Department statement said.
Blinken on his own visit to the region last year said he found credible the allegations of Rwandan support for the M23 rebels, who relaunched their armed campaign in Eastern DRC in late 2021.
Kagame denies supporting the M23 but has called for action in the lawless area against the Democratic Forces for the Liberation of Rwanda (FDLR).
Armed groups have plagued much of Eastern DR Congo for three decades, a legacy of regional wars that flared in the 1990s and 2000s.