Allies of Bashar al-Assad’s murderous regime rallied around the Syrian strongman and pledged to respond to US “aggression” after the Trump administration bombed a military airfield in retaliation for a poison gas attack.

“What America waged in an aggression on Syria is a crossing of red lines. From now on we will respond with force to any aggressor or any breach of red lines from whoever it is and America knows our ability to respond well,” officials from Russia, Iran and pro-Assad militias said in a statement Sunday.

The statement, released by the Ilam al Harbi (War Media) outlet, apparently mocked former President Obama’s warning to Assad in 2012 not to cross a “red line” with his use of chemical weapons or face a military response. Obama never carried out his threat.

And the Kremlin said Russian President Vladimir Putin and Iran’s leader Hassan Rouhani condemned the cruise-missile attack Thursday on Syria’s Shayrat airfield and urged the United Nations Security Council to take action against the US for launching the attack that violated “the sovereignty of an independent country.”

The two leaders who talked on the telephone Sunday said an impartial investigation should look into the chemical weapons attack on Syrian civilians last week.

At least 87 people were killed — including women and children — in the assault on the Syrian town of Khan Sheikhoun last Tuesday.

Horrified and outraged by images of the young victims, President Trump launched 59 Tomahawk cruise missiles Thursday at the air base where the Syrian planes carrying the sarin gas took off.

Russia has been propping up the Assad regime since September 2015 in its fight against anti-government rebels. Iran has also contributed Shiite militias to back Assad.

With Post wires