United States-led international coalition troops withdrew from Iraq's Taji military base on Sunday and handed it over to Iraqi security forces, Reuters witnesses, and the coalition said.

The base, 20 km (12 miles) north of Baghdad, had been the site of frequent rocket attacks by Iran-backed militias targeting U.S.-led troops in recent months.

"The movement of coalition military personnel is part of a long-range plan coordinated with the government of Iraq," the coalition said in a statement, adding that Camp Taji has historically held up to 2,000 coalition members, most of whom have departed this summer.

Remaining coalition troops will depart in the coming days after finalizing the handing over of equipment to Iraqi security forces, it added.

This was the eighth transfer of a coalition portion of an Iraqi base back to Iraqi forces, it said.

The withdrawal came days after U.S. President Donald Trump redoubled his promise to withdraw the few U.S. troops still in the country. The United States has had about 5,000 troops stationed in the country and coalition allies a further 2,500.

On Thursday, Trump met at the White House with Iraqi Prime Minister Mustafa al-Kadhimi, who has been praised for his efforts in reforming Iraq after mass protests over poor governance forced the previous government to resign.

The top agenda of the meeting was the discussion over the presence of American troops in Iraq, continuing months of negotiations on the issue.

While both leaders have expressed willingness to see the withdrawal of U.S. troops, al-Kadhimi acknowledged that they are needed there to help Iraqi forces fight remnants of ISIL.

Iraq's parliament had voted this year for the departure of foreign troops from Iraq, and the U.S. and other coalition troops have been leaving as part of a drawdown.

The vote came after a U.S. airstrike on Baghdad airport killed Iranian general Qassem Soleimani and Iraqi militia leader Abu Mahdi al-Muhandis.

(With input from Reuters)