Democratic Republic of Congo announced the suspension of flights from Rwanda's national carrier last Friday night. It also summoned Kigali's ambassador.
DRC spokesperson Patrick Muyaya said the strong strokes came in response to what Kinshasa says is Rwanda's support for M23 rebels carrying out a military offensive in DRC's eastern borderlands.
"A warning was made to the Rwandans, whose attitude is likely to disrupt the peace process ... where all the armed groups, except for the M23, are committed to the path to peace," Muyaya said.
The DRC spokesperson restated Kinshasa's designation of the M23 as a terrorist group, and would exclude it from negotiations being held in Kenya with militia groups active in eastern Congo.
The M23 and Kigali, in turn, have accused Congo's army of collaborating with the Democratic Forces for the Liberation of Rwanda (FDLR), a militia founded by ethnic Hutus who fled Rwanda after participating in the 1994 genocide. DRC denies this.
Rwanda's government was not immediately available for comment on Saturday.