Acting Defence Secretary Chris Miller arrived in the Middle East on Wednesday to visit US troops in the region before a drawdown to 2,500 soldiers in Iraq and Afghanistan.
Mr Miller was appointed to the position on November 9 by departing President Donald Trump after the sacking of Mark Esper, but will leave the post on January 20.
He arrived in Bahrain on Wednesday, where he was received by Defence Affairs Minister Lt Gen Abdulla bin Hassan Al Nuaimi, the country’s news agency reported.
The US Department of Defence said the purpose was to thank American troops stationed in the region and be with them for the Thanksgiving holiday on Thursday.
“Acting Secretary Miller will meet service members to express his gratitude for the selfless service to the nation by both them and their families, and to wish them a happy and healthy Thanksgiving holiday,” the department said.
Mr Miller will also meet leaders of the host countries.
The department did not say which capitals Mr Miller would visit, but Iraq and Gulf countries hosting American troops are expected to be on the itinerary.
Addressing “security interests and priorities of countering violent extremism and combating malign activities that threaten the sovereignty and stability of the region” will be on the table, the Pentagon said.
On November 17, Mr Miller announced plans to reduce US troop levels in Iraq and Afghanistan to 2,500 soldiers by January 15.
That means 500 troops will be leaving Iraq by that date.
But the US has strengthened its presence in other areas in the region.
The military this week quickly sent B-52 bombers to the Middle East in an apparent move to counter Iran.
The US Central Command said the planes were meant to “deter aggression and reassure US partners and allies".
Departing US Secretary of State Mike Pompeo returned from the region this week, where he visited the UAE, Israel, Turkey, Qatar and Saudi Arabia.