Speaking for the first time since the deadly attack on the rebel-held village of Khan Sheikhoun, Assad said there had been "no order to make any attack" adding, "even if we had (chemical weapons) we wouldn't use them".
He claimed the images of the children dying from the incident, which claimed the lives of 87 people, were "propaganda" designed to prompt a US missile strike days later.
President Assad told AFP: "Our impression is that the West, mainly the United States, is hand-in-glove with the terrorists.
Assad accused the West of 'propaganda'
They fabricated the whole story in order to have a pretext for the attack
President Bashar al-Assad
"They fabricated the whole story in order to have a pretext for the attack.
"It's not clear whether it happened or not, how can you verify a video? There are a lot of fake videos now.
"We don't know whether those dead children were killed in Khan Sheikhun. Were they dead at all?"
Boris Johnson has condemned Assad
Countries that support and oppose the missile strikes in Syria
Mon, April 10, 2017
European countries have been broadly supportive so far as President Trump ordered missile strikes against a Syrian airfield from which a deadly chemical weapons attack was launched
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SYRIA OPPOSES: President Bashar al-Assad's office denounced the U.S. strike as 'reckless, irresponsible behavior.'
Tensions are simmering between the US and
Mr Assad said he would allow what he described as an "impartial" investigation into the events at Khan Sheikhoun, to ensure it would not be used for "politicised purpose".
His comments come after Russia vetoed a UN Security Council resolution demanding swift action over Syria.
Assad has said the claims his government were responsible for the attack are 'fabricated'
It prompted Foreign Secretary Boris Johnson to hit out at Russian President Vladimir Putin for his support of Syrian Despot Bashar al-Assad’s tyrannical regime after Moscow vetoed UN action in the region.
Mr Johnson accused Russia of neglecting its “responsibilities” as a global superpower – and serving as a “lifeline” after Vladimir Putin used Russia’s veto to block the United Nations Security Council’s resolution to condemn the sarin gas attack.