As many as 450,000 civilians are trapped in Mosul's Old City, caught up in house-to-house fighting between Islamic State and Iraqi government forces and cut off from aid, the International Committee of the Red Cross (ICRC) said on Wednesday.

The Iraqi army says it is in the final stages of its campaign to rout the Islamist militants from their last major urban redoubt in Iraq, seven months after the U.S.-backed operation to recapture the city began.

Patrick Hamilton, ICRC deputy director for the Middle East, said civilians were facing "very stark choices" as food and water run out.