Confusion reigned at the Pentagon Monday amid credible reports from inside the U.S. military that preparations were underway to withdraw U.S. troops from Iraq following a U.S. strike that killed a top Iranian commander.

A letter from Marine Brig. Gen. William Seely addressed to the Iraqi military circulated on social media Monday, saying that the U.S. was “repositioning forces” for “onward movement." A U.S. defense official confirmed to Military Times on Monday that the letter from Seely, the commander of Task Force Iraq, was authentic.

A short while later, Secretary of Defense Mark Esper pushed back against the reports, telling reporters at the Pentagon Monday afternoon that the letter was not accurate and that there has been no decision to leave Iraq.

Esper said he didn’t know anything about a letter that appears to suggest preparation for troops to move out of Iraq.

But Esper did confirm that there has been some repositioning of U.S. forces.

“There’s been no decision whatsoever to leave Iraq,” the defense secretary said at the Pentagon, adding, “there’s no decision to leave, nor did we issue any plans to leave or prepare to leave.”

Esper said the U.S. remains committed to the campaign to defeat the Islamic State group in Iraq and the region.

Gen. Mark Milley, chairman of the Joint Chiefs of Staff, later told reporters the U.S. is “moving forces around” Iraq and neighboring Kuwait. He said a draft letter circulated internally by a U.S. Marine commander was a “poorly written” honest mistake that should never have gotten out.

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The draft letter appeared to suggest the U.S. was preparing to pull troops out of Iraq in response to a vote by the Iraqi Parliament over the weekend.

Milley and Esper, however, said the U.S. has been moving troops around Iraq largely due to increased security threats from Iran. The letter was meant to coordinate with the Iraqi military on an increase in U.S. helicopter and troop movements as they shift positions around the country, they said.

Milley acknowledged that some language in the letter “implies withdrawal," but said that ”is not what is happening."

“The long and the short of it is, it’s an honest mistake," he said, adding that he had just gotten off the phone with the U.S. commander in the Middle East, who explained the effort.

Some U.S. troops in Iraq are moving to safer positions, a defense official told Military Times Monday.

The U.S. is “moving some forces around to appropriately place our folks on the ground to be in very good defensive positions. We are keeping our force safe. There is no change in policy as far as a wide-scale exit.”

Army Lt. Col. Thomas Campbell, a Pentagon spokesman, told Military Times 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. We remain committed to the D-ISIS coalition and ensuring a safe, secure, and prosperous future for the Iraqi people.”

The letter said the move to get troops out of Iraq was “in due deference to the sovereignty of Iraq and as requested by the Iraqi Parliament and the Prime Minister."

“In order to conduct this task, Coalition Forces are required to take certain measures to ensure that the movement out of Iraq is conducted in a safe and efficient manner,” the letter reads.

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“During this time there will be an increase in helicopter in and around the International Zone (IZ) of Baghdad. This increased traffic will include CH-47, UH-60, and AH-64 security escort helicopters,” the letter reads.

The letter also detailed that U.S. forces would conduct these operations at night “to help alleviate any perception” that the U.S. is increasing force “into the IZ.”

Military Times has reached out to Operation Inherent Resolve, the command overseeing the U.S. mission in Iraq, and has not yet received a response.

The Iraqi parliament, upset over the death of Quds Force commander Qassem Soleimani, voted in a non-binding referendum Sunday to end the agreement that allowed U.S. troops to assist Iraqi forces in their fight against Islamic State militants.

On Sunday, U.S. Secretary of State Mike Pompeo dismissed the Iraqi Parliament’s vote on Sunday that called for U.S. troops to leave their country.

“We are confident that the Iraqi people want the United States to continue to be there to fight the counterterror campaign. And we’ll continue to do all the things we need to do to keep America safe," Pompeo said on “Fox News Sunday.

Wall Street Journal reported that President Donald Trump threatened sanctions and a repayment of billions if Iraq expelled U.S. troops from the country.

“We have a very extraordinarily expensive air base that’s there. It cost billions of dollars to build,” Trump said on Air Force One Sunday, according to the Wall Street Journal. “We’re not leaving unless they pay us back for it.”

-The Associated Press contributed to this story