US acting Defense Secretary Patrick Shanahan arrived in Baghdad on Tuesday.

It is expected for Shanahan to meet with Iraqi security officials and politicians.

He is on a tour of the Middle East, last visiting NATO trainers and military officials in Afghanistan.

President Donald Trump announced his intention to withdraw all US forces from Iraq in December. Washington has denied that pulling forces from Syria will result in a troop increase in Iraq. Officially, the United States has about 2,000 forces deployed in Syria and 5,000 in Iraq.

He then said the United States will use Iraq to watch Iran. The comments drew the ire of Iraqis across the political spectrum, citing it a violation of the Iraqi constitution.

Shanahan replaced James Mattis a defense secretary in December as Mattis announced his intention to retire this month.

The early retirement was seen in Washington as an affront to Trump's chaotic foreign policy announcements.

ISIS is defending kilometers of its so-called caliphate east of the Euphrates near the Iraqi border in Syria. A declaration of their defeat in Syria is imminent. Iraq declared ISIS defeated in December 2017.