The U.S. military said on Wednesday that it had completed the withdrawal of all American troops from Iraq.

This ends a 12-year mission against the Islamic State group.

The last troops left an air base in northern Iraq.

This followed a deal between Baghdad and Washington.

President Donald Trump called the withdrawal “orderly.”

It was finished by a Sept. 30 deadline.

He said the U.S. had been pulled into a “quagmire.”

He also said the shift was a victory for the U.S., Iraq and over the Islamic State group.

The withdrawal was agreed two years ago.

It comes during the ongoing war between the United States and Iran.

That war has sometimes spilled into Iraq.

Iran-backed militias have fired on U.S. troops, and the U.S. has struck their strongholds.

Trump compared his decision to launch the Iran war to the Iraq war.

He said his one-day action in Venezuela and the Iran war took less time.

He also said they caused fewer U.S. troop deaths.

Baghdad called the end of the U.S. mission a sign of its growing strength and sovereignty.

Iran-backed groups also celebrated.

But some Iraqis, especially in the Kurdish region, fear a resurgence of the Islamic State group.

They also fear more attacks by Iran-linked groups.

Pentagon spokesperson Sean Parnell said troops and equipment had completed an “orderly departure” from the Irbil air base.

He said the U.S. would keep providing targeted training and intelligence support to Iraqi partners.

Iraqi Prime Minister Ali al-Zaidi presided over the handover ceremony.

He described the withdrawal as the start of a “new phase” defined by Iraq’s sovereignty.

He said Iraqi forces would keep fighting the Islamic State group.

He also said non-state groups would no longer hold weapons.

Trump praised al-Zaidi and said he had endorsed him, though al-Zaidi was not on a ballot.

U.S. troops invaded Iraq in 2003, left in 2011, and returned in 2014 to fight the Islamic State group.