An unconscious Syrian child receives treatment at a hospital in Khan Sheikhun, a rebel-held town in the northwestern Syrian Idlib province, following a suspected toxic gas attack on April 4, 2017. Picture: AFP / Omar haj kadour.

Press Secretary Sean Spicer issued a statement on Monday saying Washington had “identified potential preparations for another chemical weapons attack by the Assad regime that would likely result in mass murder of civilians, including innocent children”.

It warned Syrian President Bashar al-Assad that he and his military will “pay a heavy price” if it conducts such an attack.

“As we have previously stated, the United States is in Syria to eliminate the Islamic State of Iraq and Syria.

“If, however, Mr. Assad conducts another mass murder attack using chemical weapons, he and his military will pay a heavy price.”

Syrian President Bashar al-Assad during an interview with AFP in Damascus, 2014. Picture: AFP / Joseph Eid.Source:AFP

The White House revealed the preparations by Syria were similar to those undertaken before an April 4 chemical attack that killed dozens of civilians, including children, and prompted President Donald Trump to order a cruise missile strike on a Syrian air base.

Mr Trump ordered the strike on the Shayrat airfield in Syria in April in reaction to what Washington said was a poison gas attack by Assad’s government that killed at least 70 people in rebel-held territory. Syria denied it carried out the attack.

The strike put Washington in confrontation with Russia, which has advisers in Syria aiding its close ally Assad.

US officials at the time called the intervention a “one-off” intended to deter future chemical weapons attacks and not an expansion of the US role in the Syrian war.

Assad, backed by his ally Russia, has strongly denied the allegation that his forces used chemical weapons against the rebel-held town of Khan Sheikhun, describing it as a “100 per cent fabrication”.

He has repeatedly said that his forces turned over all chemical weapons stockpiles in 2013, under a deal brokered by Russia to avoid threatened US military action.

The agreement was later enshrined in a United Nations Security Council resolution.

But US Defense Secretary Jim Mattis previously warned that there was “no doubt” that Syria had in fact retained some chemical weapons. An Israeli military assessment also found that Assad’s regime was still in possession of “a few tonnes” of chemical weapons.

A Syrian child receives treatment at a small hospital in the town of Maaret al-Noman following a suspected toxic gas attack in Khan Sheikhun, a nearby rebel-held town in Syria’s northwestern Idlib province in April this year. Picture: AFP / Mohamed al-BakourSource:AFP

US President Donald Trump delivers a statement on Syria from the Mar-a-Lago estate in West Palm Beach, Florida, on April 6, 2017. Trump ordered a massive military strike against a Syria Thursday in retaliation for a chemical weapons attack they blame on President Bashar al-Assad. Picture: AFP/ Jim Watson.Source:AFP

The US-led coalition and allied fighters are battling to oust the IS group from its Syrian bastion Raqa.

The coalition is also backing a major assault on the last IS-held pockets of Mosul in neighbouring Iraq.

Russia is flying a bombing campaign in Syria in support of Assad, while the US is heading a coalition mainly targeting IS.

Neither Washington, which backs the opposition, nor Moscow, a longtime ally of the Syrian regime, have managed to find a solution to the conflict.

Syria’s war began in March 2011 with anti-government protests that spiralled into a complex and devastating conflict that has killed more than 320,000 people.

Rebels are now on the back foot after regime advances with support from allies Russia and Iran.

— with wires

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