The International Criminal Court in the Netherlands said last week that it would rule tomorrow on the chief prosecutor's request for an arrest warrant for Bashir for atrocities committed in Darfur's six-year war.
Prosecutors at the court - the world's first permanent war crimes tribunal - alleged in July that the Sudanese leader was guilty of genocide, war crimes and crimes against humanity for masterminding a campaign of murder, torture and rape by government troops and Arab militias.
Sudanese ministers have said they will ignore any warrant, and Le Roy said UN peacekeepers have no mandate to arrest Bashir "so we will not take that kind of action."
There are 13,000 UN and African Union peacekeepers in Darfur and a 13,000-strong UN mission in semiautonomous southern Sudan enforcing a 2005 agreement that ended decades of fighting in that region.
"We don't fear that the UN mission will be specifically targeted by any group," Le Roy said.
"I'm sure there will be some crowd movements. There will be some violence here and there. What we don't know is the level of violence, and we hope the government of Sudan will act responsibly to make sure that all beginning of violence will be stopped in due time."
