Rwanda has closed part of its border with DR Congo over the Ebola crisis.
At least two people have died from the virus in the eastern Congolese city of Goma, near the Rwandan border.
It is one year today that DR Congo declared what has become its worst outbreak, with more than 1,800 people dead and over 2,700 infected.
The outbreak is the most complicated ever as it is happening in an active conflict zone, BBC Africa correspondent Anne Soy says.
In a statement, the Congolese presidency said there had been a “unilateral decision by the Rwandan authorities” to close the crossing at Goma.
“The Congolese authorities deplore this decision, which runs counter to the advice of the WHO (World Health Organisation),” the statement said.
The WHO has previously warned against trying to contain the virus by restricting travel or trade.
Last week, the WHO designated the outbreak a global health emergency. It is the highest level of alarm the organisation can sound and which has only been used four times previously – including during the Ebola epidemic that killed more than 11,000 people in West Africa between 2014 to 2016.