The United States is to withdraw more than a third of its troops from Iraq this month, the top American commander for the Middle East has said.
General Frank McKenzie, commander of US Central Command, said the number of troops deployed to the country will go down from 5,200 to 3,000 in the coming weeks.
A number of British personnel left the country in March.
President Donald Trump has previously promised to remove the US from "endless wars".
Gen McKenzie said the reduction in Iraq reflects American confidence in the ability of US-trained Iraqi security forces to handle the threat from so-called Islamic State (IS or ISIS).
An announcement on a further personnel withdrawal from Afghanistan is expected in due course, after thousands left the country earlier this year.
"In recognition of the great progress the Iraqi forces have made and in consultation and co-ordination with the government of Iraq and our coalition partners, the United States has decided to reduce our troop presence in Iraq from about 5,200 to 3,000 troops during the month of September," Gen McKenzie said.
He added the remaining US troops in Iraq would continue advising and assisting Iraqi security forces in their fight against IS.
"The US decision is a clear demonstration of our continued commitment to the ultimate goal, which is an Iraqi security force that is capable of preventing an ISIS resurgence and of securing Iraq’s sovereignty without external assistance,” Mr McKenzie said.
"The journey has been difficult, the sacrifice has been great, but the progress has been significant."
Tobias Ellwood, chair of the Defence Select Committee, told BFBS Sitrep he would "hesitate to agree" with the Americans' decision to withdraw.
"The fact that we've been in Iraq and we've been in Afghanistan so long brings a question about the post-operational stabilisation plans," he said.
"We do not have a good track record of, once we've defeated the enemy, enabling the locals - the indigenous people - to be able to stand on their own feet and that's caused consequential problems, which also lead to issues across Europe, not least with migration and so forth, because we didn't conclude the job or didn't do a good enough job in the first place."
He added: "I'd like to ensure that we don't leave a vacuum in any part of the world which could be filled by our competitors who may have a very different agenda."
The United States invaded Iraq in 2003 before leaving eight years later, but returned in 2014 after the presence of IS grew in the country.
In January, a US drone strike near Baghdad airport killed Iranian General Qassem Soleimani and Iraqi militia leader Abu Mahdi al-Muhandis.
A non-binding resolution to oust all US-led coalition forces from the country was later passed by Iraqi politicians.
In response to the Soleimani killing, Iran launched a ballistic missile attack on al-Asad air base in Iraq on 8 January, which resulted in brain injuries to more than 100 American troops.
In March, the US carried out air strikes in Iraq after a base hosting coalition forces was attacked, killing a British Army medic and two American service members.
That same month, a number of British military personnel left Iraq due to a reduced requirement during the coronavirus pandemic.
The UK began training Iraqi forces as part of a US-led coalition mission in 2014, with hundreds of troops stationed in Iraq across several sites prior to the March withdrawal.
As part of Operation Shader, British troops have trained more than 100,000 Iraqi and Kurdish Peshmerga forces in weapons maintenance, counter IED, medical and engineering skills.
Cover image: American troops in Iraq (Picture: PA).