CAMP TAJI, IRAQ (REUTERS) - United States-led international coalition troops withdrew from Iraq's Taji military base on Sunday (Aug 23) and handed it over to Iraqi security forces, Reuters witnesses and the coalition said.

The base, 20km north of Baghdad, had been the site of frequent rocket attacks by Iran-backed militias targeting US-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 finalising 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 US President Donald Trump redoubled his promise to withdraw the few US 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.

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

The vote came after a US air strike on Baghdad airport killed Iranian general Qassem Soleimani and Iraqi militia leader Abu Mahdi al-Muhandis.