Updated at 7:43 p.m. ET
Secretary of Defense Mark Esper announced on Monday that some forces are being repositioned inside Iraq, not leaving the country.
Two other U.S. officials told NPR that some are going to Kuwait temporarily.
The troop movement — signaled by heavy helicopter traffic out of a U.S. base in central Baghdad — was coupled with confusion about a letter sent by the U.S. military to Iraqi officials. That letter said the movements were in response to the Iraqi call for U.S. forces to leave the country, and the letter implied a withdrawal was underway. Late Monday, Gen. Mark Milley, chairman of the Joint Chiefs of Staff, told reporters that the letter was "poorly worded."
Esper also told reporters at the Pentagon that an Iraqi parliament vote on Sunday to expel U.S. troops was nonbinding and that there are no plans to leave Iraq yet.
The Pentagon press office underscored the message, saying in a tweet, "There has been no change in US policy with regard to our force presence in Iraq. We continue to consult with the Iraqi government regarding the defeat-ISIS mission and efforts to support the Iraqi Security Forces."
A U.S. military official in Iraq told NPR that the troops would be moved to "other, safer countries" while training missions were suspended. He added that most are coalition and NATO forces, not American.
A letter from Brig. Gen. William Seely to the director of the Iraqi joint operations task force informed the Iraqi government that the U.S. would be "repositioning forces over the coming days and weeks to prepare for onward movement."
The military official said the operation involved several hundred troops, mostly coalition and NATO forces being moved from the main military base in Baghdad's Green Zone. The base had been a frequent target of rocket attacks.
Top administration officials are scheduled to brief all House members on the unfolding events in Iran and Iraq on Wednesday, a Democratic aide told NPR.
Esper, Pompeo, CIA Director Gina Haspel, Joint Chiefs of Staff Chairman Mark Milley and Acting Director of National Intelligence Joseph Maguire will brief the House in a closed-door session.
Administration officials are scheduled brief senators on Wednesday.
Iraqi lawmakers passed a resolution on Sunday calling for all foreign troops to leave the country.
NPR's Tom Bowman reported that there are about 5,000 U.S. troops in Iraq, helping in the fight against ISIS there. But U.S. military officials said they would halt those efforts while bracing for retaliation from Iran.
The rising tensions stem from a U.S. drone strike that killed top Iranian Gen. Qassem Soleimani and several others last week — a move that Iran said was a violation of the country's sovereignty. Iran has vowed to avenge.
Secretary of State Mike Pompeo said he hopes the Iraqi parliament will reconsider its decision.
Meanwhile, President Trump threatened Baghdad with sanctions if U.S. forces were required to leave the country.
This is a developing story. Some things reported by the media will later turn out to be wrong. We will focus on reports from officials, credible news outlets and reporters who are at the scene. We will update as the situation develops.
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