BAGHDAD: Iraq has for the first time deployed troops trained by the U.S.-led coalition in their campaign to retake the city of Ramadi from ISIS militants, sending 3,000 of them in recent days, a Pentagon spokesman said Thursday.

Colonel Steve Warren told reporters traveling with U.S. Defense Secretary Ash Carter that 500 Sunni tribesmen, whose training by Iraqis was overseen by U.S. troops, were also taking part in the operation. He declined to say how many Iraqi forces in total were involved in the Ramadi operation.

The Iraqi forces, backed by U.S.-led coalition airstrikes, were in the process of encircling Ramadi, the capital of Anbar province, in an effort to choke off ISIS supplies and trap their fighters, ahead of a push to seize the city, Warren said.

ISIS seized Anbar’s capital Ramadi two months ago, extending its control over the Euphrates valley west of Baghdad and dealing a major setback to Prime Minister Haider al-Abadi and the U.S.-backed army which he entrusted with its defense.

Carter, on his first visit since taking up his post in February, met U.S. commanders as well as Iraqi political leaders, including Abadi.

He was briefed by Iraqi officials on the deployment of the coalition-trained troops.

Carter has criticized Iraqi forces in the past for lacking a will to fight in Ramadi. He praised Abadi and Iraqi troops Thursday but also stressed that U.S.-led coalition airpower needed to be complemented by “capable ground forces.”

“And getting those forces, in turn, requires inclusive governance,” Carter said during his meeting with Abadi.

The loss of Ramadi was the Iraqi army’s worst defeat since ISIS militants swept through north Iraq last summer and raised questions about the ability of the Shiite-led government in Baghdad to overcome the sectarian divide that has helped fuel the ISIS’ expansion in Anbar.

U.S. President Barack Obama responded last month by ordering 450 more U.S. troops to set up at Taqaddum base, which is closer to the fighting in Anbar province and only about 15 miles (25 kilometers) from Ramadi.

One of the goals of a new U.S. deployment to Taqaddum is to encourage Sunni tribes to join the battle against ISIS, complementing efforts at the Ain al-Asad air base, also in Anbar.

The Iraqi forces, backed by U.S.-led coalition airstrikes, were in the process of encircling Ramadi in an effort to choke off ISIS supplies and trap their fighters, ahead of a push to seize the city, Warren said.

Citing Iraqi battlefield reporting, Warren said Iraqi forces had advanced to the area around the University of Anbar in Ramadi, saying they were moving “methodically, deliberately and slowly.”

The United States estimates there are about 1,000 to 2,000 ISIS fighters in Ramadi, Warren said.

Shiite militia commanders, who have led much of the fightback in Iraq against ISIS over the last 12 months, have said their initial focus is not on Ramadi, but the nearby city of Fallujah, under insurgent control for more than a year and a half.

Warren said that the government in Baghdad had indicated the militia wouldn’t be involved in Ramadi.

“The government of Iraq has indicated that they have no intention of using the Shiite militia forces as part of the liberation of Ramadi,” Warren said.