The court’s chief prosecutor, Luis Moreno Ocampo, is expected to make the announcement shortly, and will brief the United Nations about his plans later this month in New York, according to an Associated Press report.
The ICC has been looking into the situation in Darfur since the United Nations in April handed it allegations of rape, murder and plunder, the first time the Security Council referred a case to the body.
The investigation would be the court’s largest and most important since it was launched almost three years ago.
UN Secretary General Kofi Annan has given the ICC the names of 51 suspected war criminals.
The Darfur region is wracked by conflict which has claimed an estimated 180,000 lives, many of these from hunger and disease.
Another two million people have been displaced since the conflict began in February 2003, when rebels took up arms against what they saw as years of state neglect and discrimination against Sudanese of African origin.
A UN inquiry in January found that Sudanese government forces and militias had committed abuses including murder, torture, rape and pillage in the suppression of the two-year-old ethnic minority uprising in Darfur.
The probe found that, while it could not be defined as genocide, war crimes took place in a systematic way in the province.
The UN Security Council in early April called for the 51 named suspects, including senior officials, to face prosecution before the ICC, overriding strong opposition from Khartoum.
The Sudanese government has vowed to defy the prosecution demand, and has said it will refuse to hand over its citizens for trial abroad, and will prosecute suspects itself.