Iraq has for the first time deployed soldiers trained by the U.S.-led coalition in their campaign to retake the city of Ramadi from Islamic State of Iraq and Syria (ISIS) militants, the U.S. military said on Thursday. The disclosure came during an unannounced visit by U.S. Defense Secretary Ash Carter to Baghdad, where he met Iraqi Prime Minister Haider al-Abadi and underscored the need for capable Iraqi ground forces to battle back ISIS. "We're making some progress. We need to make more," Carter told U.S. troops gathered at Baghdad airport. 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 Abadi and the U.S.-backed army he entrusted with its defense. The fall 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 ISIS' expansion in the Sunni heartland of Anbar. Pentagon spokesman Colonel Steve Warren told reporters travelling with Carter that the roughly 3,000 coalition-trained soldiers joined the Ramadi operation in recent days. Some 500 Sunni tribesmen were also participating, Warren said. He declined to say how many Iraqi forces in total were involved in the Ramadi campaign, citing operational security. U.S. President Barack Obama responded to the fall of Ramadi 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 km) from Ramadi. One of the goals of the new U.S. deployment to Taqaddum was to encourage Sunni tribes to join the battle against ISIS, complementing efforts at the Ain al-Asad air base, also in Anbar. Carter sought to underscore that objective in Baghdad, holding talks with Sunni leaders including the governor of Anbar province.