Hundreds of Iraqi protesters have broken down the gate of the US embassy in Baghdad in an attempt to storm the compound - an attack Donald Trump has claimed was orchestrated by Iran.

US Defence Secretary Mark Esper said the Pentagon was sending extra forces to support personnel at the embassy, while Mr Trump spoke with Iraq's prime minister to "emphasise" the need for US facilities to be protected in the country.

Secretary of State Mike Pompeo said the US "will protect and defend Americans in Iraq" during a phone conversation with Iraqi leaders, adding that extra marines would be deployed.

The protests began after Iraq condemned Washington for the strikes, which left American forces on alert for possible reprisal attacks.

The developments represent a major downturn in Iraq-US relations that could further undermine US influence in the region and weaken Washington's hand in its campaign against Iran.


Image: Protesters set fire to a reception building in the compound

Image: Fires broke out as crowds attempted to storm the embassy

Tehran has rejected accusations it was behind the violent protests at the embassy, where gunfire was heard and demonstrators were heard shouting "death to America" as they pelted the compound with stones.

The US State Department said reports from Iraqi officials that the US ambassador had been evacuated from the site in Baghdad were false. It said all US personnel at the embassy were safe and there were no plans to evacuate the site.

Matt Tueller, the envoy, had been on previously scheduled personal travel and was returning to the embassy, an official said.

Protests rage at US embassy in Baghdad

The US president spoke with the Iraqi Prime Minister Adel Abd al-Mahdi to discuss protecting US personnel and facilities.

The White House said in a statement: "The two leaders discussed regional security issues and President Trump emphasised the need to protect United States personnel and facilities in Iraq."

Responding to images on Twitter, Mr Trump had tweeted earlier: "Iran killed an American contractor, wounding many. We strongly responded, and always will. Now Iran is orchestrating an attack on the U.S. Embassy in Iraq. They will be held fully responsible. In addition, we expect Iraq to use its forces to protect the Embassy, and so notified!"

He wrote in a follow up tweet hours later: "To those who want freedom and who don't want to be dominated and controlled by Iran, this is your time!"

Image: Smoke has been seen rising from the compound

Image: Protesters broke down the gate at the compound

Iran's foreign ministry spokesman Abbas Mousavi said in a statement: "America has the surprising audacity of attributing to Iran the protests of the Iraqi people against (Washington's) savage killing of at least 25 Iraqis."

Crowds had been gathering outside the entrance to the compound for hours over controversial American airstrikes that killed more than two-dozen fighters from an Iran-backed militia over the weekend.

Gunfire was heard and there were reports of tear gas, with Reuters news agency saying 12 people involved in the protests have been injured.

Protesters, many of them in militia uniforms, shouted "down, down USA!", "death to America!" and "death to Israel!" outside the compound on Tuesday.

Image: A large crowd gathered outside the building

Image: The crowds have been gathering since the US strikes on Sunday

They also pelted the entrance with stones as they chanted: "No, no America! No, no Trump!".

Militia members later set fire to a reception area after forcing their way into the site, and several US soldiers were seen on the roof of the main building.

Iraqi special forces were sent to the scene in a bid to prevent the protesters entering the embassy and a man on a loudspeaker urged the crowd to desist, saying: "The message was delivered."

US attacks Iran-backed militia in Iraq

Image: Iraqis walk on a US national flag to denounce the strikes

The Iraqi prime minister urged the protesters to leave and warned against any aggression towards foreign embassies and representatives.

Qais al Khazali, leader of the Iranian-backed Asaib Ahl al-Haq militia, and many other senior militia leaders are among the protesters who have gathered over the past few days.

Image: The now-destroyed headquarters of the Kataib Hezbollah militia in western Iraq

Image: This protest sign reads: 'Close the American embassy otherwise people will close it'

Kataib Hezbollah flags have also been hung on the fence surrounding the building in a show of support, and graffiti has been sprayed on walls.

The Kataib Hezbollah is the militia that was targeted by the deadly US strikes in the west of Iraq on Sunday, which caused at least 25 deaths and injured another 55 people.

Sky News' foreign affairs editor Deborah Haynes said: "It's revived the absolute hatred many Iraqis feel about having US forces on their soil at all.

"That's in the wake of the 2003 invasion and subsequent occupation of Iraq, they remember all too well those days.

"US forces were actually welcomed back in 2014, by the government, to help in the fight against Islamic State (IS) and during that time they worked on the same side as these paramilitary groups, many backed by Iran, because they had a shared enemy in IS."

Image: Iraqis burn a US national flag

The US airstrikes also prompted the Iraqi national security council to say it would reconsider working with the US-led coalition against Islamic State.

US, British and other foreign troops are only able to operate in Iraq with the permission of the government, and any review of the relationship could lead to permission being withdrawn.

US troops and Iranian-backed militias have largely avoided direct confrontation in Iraq over the past five years as they both fought a common enemy in Islamic State.

But a growing, global standoff between Washington and Tehran over Iran's nuclear ambitions could see a flare up in hostilities on the ground in Iraq where both countries have a lot of interests, personnel and influence.

More than 5,000 US military personnel are based in Iraq as well as some 400 British forces.