Iraq forces have surrounded the city of Ramadi and are preparing for a final assault in what will be the first significant test of American-trained forces against the Islamic State, according a senior official with the U.S.-led coalition that is supporting the mission.

Iraqi forces plan to tighten a cordon around the city to cut escape routes before launching a final operation to clear militants out of the city, according to the senior official, who closely monitors the fighting. He asked not to be named because he is not authorized to speak publicly about the operation.

The official said that airstrikes by the coalition and Iraqi ground operations have severely weakened Islamic State forces inside the city. That may allow Iraqi forces to avoid a prolonged street battle with major casualties that military planners have feared. […]