The court said it had received an independent medical report of the 90-year-old's fitness to stand trial, and will hold further hearings on the issue later this month.
Kabuga went on trial in September last year, with prosecutors accusing him of setting up hate media that urged ethnic Hutus to kill rival Tutsis and supplying death squads with machetes.
The businessman refused to appear in court or appear remotely at the start of his trial and has subsequently followed proceedings via video-link from a wheelchair at the court's detention center.
"It is appropriate to maintain the stay of evidentiary hearings pending the resolution of the issue of Mr. Kabuga's fitness to stand trial," presiding judge Iain Bonomy said in a court order.
The three medical experts who compiled the report have now been asked to give their testimonies before the judges, starting next week until March 29, to guide the court's decision "on the future course of this trial," Bonomy said.
The prosecution and defense will address the court on the issue afterwards, the judge added.
Kabuga was arrested in Paris in 2020 after decades on the run and sent for trial in The Hague.
He has pleaded not guilty to charges of being involved in an infamous Hutu radical radio station urging people to kill Tutsi "cockroaches" during the 1994 slaughter in which 800,000 people died.
He also denied supplying machetes and otherwise supporting the murderous Interahamwe Hutu militia.
Health Halts Rwanda Genocide Trial
FILE: Felicien Kabuga, an alleged financier of the 1994 genocide in Rwanda, at The Hague, Aug. 18, 2022, in this screengrab released by The Mechanism for International Criminal Tribunals (MICT).
THE HAGUE - UN judges on Friday put Rwandan genocide suspect Felicien Kabuga's trial on hold while they resolve whether he is in good enough health to remain in the dock.