Haley, prior to the chemical attack, had said, "Our priority is no longer to sit there and focus on getting Assad out".
Mr Putin's decision to host Mr Tillerson signalled Moscow's intent to maintain communication with the U.S. even as the countries bash each other publicly in louder and louder tones.
Mr. Mattis reiterated that the US would strike against the Bashar al-Assad regime in Syria again if it used chemical weapons.
Russian Federation has once again denounced what it called "an act of aggression", after the USA missile strike on a Syrian airbase in retaliation to a reported use of chemical weapons in Khan Sheikhoun.
Trumps comments come less than a week after he ordered missile strikes on a Syrian airfield after US evidence indicated that Assad killed civilians using the nerve agent sarin.
He also rejected American claims of incontrovertible evidence that Assad ordered the chemical attack.
Responding to a question about the danger of their antagonistic positions related to Syria spiralling into "a conflict between the two nuclear-powered countries", Mr. Mattis said during a briefing at the Pentagon: "It will not spiral out of control".
Two days after, the United States launched 59 cruise missiles against the Shairat military base in central Syria, where from, according to the USA, airplanes carrying chemical weapons took off.
Diplomats said that Russian Federation has put forward a rival draft resolution that expresses concern at last week's gas attack and condemns the US strike on Syria.
His comments came moments before President Donald Trump said relations with Russian Federation had reached a "all-time low".
President Vladimir Putin's meeting with U.S. Secretary of State Rex Tillerson hasn't produced any positive shift yet in Russia-U.S. relations, the Kremlin said Thursday.
He said working groups would be established to improve U.S.
"It is clear to us the reign of the Assad family is coming to an end", he told reporters in Italy.
"So I am dismayed that Russian Federation has once again blocked the UN Security Council and in so doing refused to condemn the use of chemical weapons or support a full UN investigation into the attack".
And the USA warned Russian Federation that it is only isolating itself with its continued support of Assad.
Following talks that also involved Vladimir Putin, Tillerson announced that "There is a low level of trust between our two countries", and things only got more tense from there.
It is not the first time Mr Putin and Mr Tillerson have had talks.