Allegations that Syrian forces had deliberately poisoned civilians were "100 per cent fabrication", the president said on Thursday, adding that the Syrian government gave up its chemical weapons stocks as part of a 2013 agreement.
The Wall Street Journal cited Trump as saying that Assad's use of chemical weapons again would elicit another military response, but he also said he would not intervene in depth in the conflict.
Washington has blamed the Syrian government for launching a deadly chemical attack in Khan Sheikhun that killed more than 80 people on April 4, and responded by striking a Syrian air base.
In a news conference following talks with visiting U.S. Secretary of State Rex Tillerson and a two-hour joint meeting Russian President Vladimir Putin, Russian Foreign Minister Sergei Lavrov said the discussions were fruitful, underlining good prospects for future joint work.
The Organisation for the Prohibition of Chemical Weapons has begun an investigation into the Khan Sheikhun incident, but Russian Federation on Wednesday blocked a UN Security Council resolution demanding that Syria cooperate with the probe. Russian Federation accused the United States of breaking worldwide law with the strike against the Syrian regime, a key ally that Moscow has supported with air strikes since 2015.
Tillerson's stance changed after the attack on Idlib province, and he said Thursday the United States is part of an worldwide coalition to remove Assad via a political process.
I think I understand the Trump administration's Syria policy.
"The current state of US-Russia relations is at a low point", Tillerson said.
Bucks playoff series with Toronto is set
He missed 21 games before returning to play the last four of the regular-season - his only game experience with Ibaka and Tucker. Toronto was the third-best post-All Star defense in the league thanks in large part to the versatility those two provide.
China typically sides with Russian Federation in the Security Council, including in opposing US -backed measures to punish Syria for its use of chemical weapons.
Assad said more USA attacks "could happen anytime, anywhere, not only in Syria". Were they dead at all?"He insisted several times that his forces had turned over all chemical weapons stockpiles in 2013, under a deal brokered by Russian Federation to avoid threatened United States military action". Secretary of State Rex Tillerson said the US sees "no further role" for Bashar al-Assad as Syria's leader.
Mr Tillerson said there was "a low level of trust" between both countries and such a relationship could not be allowed to continue between the world's foremost nuclear powers.
Global investigators have concluded that Sarin, chlorine and sulphur mustard gas have been used in Syria's six-year-old conflict, with government forces using chlorine and Islamic State militants using sulphur mustard.
The two sides spoke of the low-level of trust between them and the US, noting it's an unacceptable state of strain between the world's two biggest nuclear powers.
Assad said the US and Syria could still be allies "if they are serious in fighting terrorists". Russian Federation is a strong country. We don't have any chemical weapons.
"We need to find out the facts, conduct a comprehensive investigation", Russia's Safronkov told the council.
U.S. Ambassador Ward insisted it was a deliberate attack that amounted to "a direct affront to the Chemical Weapons Convention and, indeed, a direct affront to human decency, carried out by a State Party" to the OPCW, according to the text of his speech that was posted on the organization's website.