A Rwandan judge has ordered the terror trial of opposition leader Victoire Ingabire to proceed.
She is accused of propagating ethnic hatred and "genocide revisionism" - charges she says are politically motivated.
The prosecution wanted the trial to be postponed until more evidence arrived from the Netherlands, where Ms Ingabire lived until January 2010.
She was arrested in April and barred from standing in last year's election.
She appeared in court in handcuffs, wearing the standard pink Rwandan prison uniform and with her head shaved.
The BBC's Geoffrey Mutagoma in Kigali says it is common for Rwandan prisoners to have their heads shaved for hygiene reasons.
Her British lawyer Iain Edwards argued for the trial to proceed as planned and judge Alice Rulisa agreed.
"The prosecutor has said from the beginning that they were ready to proceed, and that they had all the evidence they needed to prosecute this case," she said.
"Now they are saying they need more time."
The trial has already been delayed on two occasions.
The Unified Democratic Forces party leader is accused of colluding with an ex-officer of a Hutu militia to buy and distribute weapons to threaten national security.
Ms Ingabire said the charges were a fabrication and politically motivated.
If she is found guilty of all the charges, she is likely to get a life sentence, our reporter says.
Ms Ingabire is a Hutu and most of the 800,000 people killed in the 1994 conflict were ethnic Tutsis.
President Paul Kagame, the former rebel leader whose Tutsi-dominated Rwandan Patriotic Front (RPF) put an end to the genocide, won a second term in office in August 2010 with 93% of the vote.