U.S. Defense Secretary, Ashton Carter, made an unannounced visit to Iraq on Thursday, July 23 morning as American and Iraqi military officials finished plans for an assault meant to retake Ramadi from the Sunni militant group known as the Islamic State, the New YorkTimes reports.

Iraqi security forces, backed by American airstrikes, have in recent days begun conducting what a senior American military official called “shaping” and “isolating” operations around Ramadi, a pivotal city about 65 miles west of Baghdad. The Iraqis have several thousand troops ready to attack the city.

“When conditions are right, we will transition into an assault to seize Ramadi,” Col. Steve Warren, a Defense Department spokesman, told reporters shortly before Carter arrived in Iraq. “This is classic maneuver warfare.”

Colonel Warren said the direct assault would begin within one to eight weeks; he declined to be more specific, according to the NYT.

Carter is making his first visit to Iraq as secretary of defense. He plans to discuss the looming assault with Iraqi officials and with Americans involved in training the Iraqi Army.