The US military has confirmed carrying out air strikes in Syria's Deir Ezzor, apparently targeting facilities used by groups affiliated with Iran's Revolutionary Guards Corps (IRGC).

The strikes on Tuesday came even as the United States aimed to respond to a draft agreement proposed by the European Union that would bring back the 2015 nuclear deal with Iran that former president Donald Trump abandoned and current President Joe Biden has sought to revive.

The military's Central Command said in a statement that such strikes were aimed at protecting US forces from attack by Iran-backed groups.

It cited one such incident on August 15, which Reuters has reported involved a drone attack on a compound run by the coalition, with no casualties.

"The president gave the direction for these strikes," said spokesperson Army Colonel Joe Buccino.

Central Command called the strikes a "proportionate, deliberate action intended to limit the risk of escalation and minimize the risk of casualties."

No mention of casualties

The statement about Tuesday's US strike did not mention whether there were any casualties and did not say whether the air strikes were carried out by manned or unmanned aircraft.

This is not the first time US warplanes have struck Iran-backed forces in Iraq and Syria. The United States hit operational and weapons storage facilities at two locations in Syria and one in Iraq in June last year.

US forces first deployed into Syria during the Obama administration's campaign against Daesh, partnering with the PYD/YPG-dominated SDF militia. 

The YPG is the Syrian offshoot of the PKK terrorist organization. In its almost 40-year terror campaign against the Turkish state, more than 40,000 people have been killed. Türkiye, the US, and the EU recognize the PKK as a terrorist organization.

There are about 900 US troops in Syria, most of them in the east.

But Iran-backed militias established a foothold in Syria while fighting in support of Syria's regime leader Bashar al Assad during the civil war.

Iran-backed militias are heavily concentrated west of the Euphrates in Deir Ezzor province, where they get supplies from Iraq through the al Bukamal border crossing.