"We have the green light for the visit, but we don't yet know when it will take place," ICRC President Jakob Kellenberger told the Swiss newspaper Tribune de Geneve.
"There is no reason we cannot do it," he added in the interview.
Technical arrangements for the visit by aid workers to check on Saddam Hussein's treatment in prison were still being made, according to the humanitarian agency.
"There has been a formal indication from the United States. We think a visit ought to take place as soon as possible," ICRC spokesman Florian Westphal said.
The ICRC oversees the Third Geneva Convention, an internationally-recognised set of rules which guarantee minimum standards of treatment for prisoners of war and detainees, including the right to visits from its aid workers.
The US formally accepted last month that Saddam
Hussein, who was captured by US troops in Iraq on December 13, was a prisoner of war and the Red Cross had publicly called several times to see him.