The warnings were exchanged after the United States and several European countries threatened to utilize military action against the Syrian government and its main ally, Russia, in response to a suspected chemical weapons attack over the rebel-held town of Douma.
During the West Wing sitdown, Defense Secretary James Mattis and the Chairman of the Joint Chiefs of Staff Joe Dunford were expected to lay out options for retaliatory strikes against the Syrian regime.
That meant airstrikes, possibly in tandem with France and other allies that have expressed outrage at the alleged Syrian chemical attack, could be launched within hours of a presidential decision. "On Thursday, Mr. Trump tweeted that missiles, "new" and "'smart'" are coming.
Inspectors from an worldwide chemical weapons watchdog are preparing to begin collecting samples Saturday in Douma, Syria, the site of a recent alleged chemical weapons attack blamed on the forces of Syrian President Bashar al-Assad.
Those comments were similar to those of Senator Elizabeth Warren of MA who tweeted "Chemical attacks in Syria are horrifying, and a clear violation of global law".
Although Mattis noted that military action carried risks, he also emphasized that Syrian use of chemical weapons should not be tolerated.
Mr Trump said the U.S. was not seeking an "indefinite presence" in Syria.
"This time, our allies and we have struck harder", he said.
"I'm not ready to speculate that that would happen", Mattis said.
Russian Federation has warned the U.S. that launching air strikes in response to a suspected chemical attack in Syria could spark a war between the two countries. "Russia vows to shoot down any and all missiles fired at Syria", Trump wrote. "Get ready Russian Federation, because they will be coming, nice and new and 'smart!' You shouldn't be partners with a Gas Killing Animal who kills his people and enjoys it!"
The battered and technologically inferior Syrian air force would not be capable of significant defensive efforts against a US -led attack.
"We are continuing to assess intelligence and are engaged in conversations with our partners and allies", the statement said. "We're still working on this". Ample crude supplies had pared some of the gains on Thursday, though crude futures remained in touching distance of levels not seen in more than three years.
"The position is a very risky one because of Russian involvement, also because we have an erratic president of the United States".
But since then, Mr. Trump has backed off slightly, and rebuffed claims that he has given away the timetable on a Syria response - something he accused former President Barack Obama of doing.
He said the other two targets were storage facilities for chemical weapons and equipment near the central city of Homs, with one of the targets also containing "an important command post". We are totally predictable.
"No final decision has been made", White House press secretary said.
The prospect of Western military action in Syria that could lead to confrontation with Russian Federation hung over the Middle East on Friday but there was no clear sign that a US-led attack was imminent.
The Russian military said it had observed movements of US Navy forces in the Gulf. "We pray that God will guide the whole region toward a future of dignity and of peace".
Ms Maria Zakharova, spokesman for the Foreign Ministry, called statements from Washington "militaristic", and said the world should think seriously about the possible consequences of threats.
Britain continues to support the US-led coalition targeting IS jihadists in Iraq and Syria, and has conducted more than 1,700 strikes.
The linking of the Russian air defense picture in Syria-informed by modern and highly capable radars such as those found on Russian naval ships and the feared S-400 system at Latakia-to the Syrian regime's own Russian-supplied air defense system means that the missile batteries that would oppose any US -led strike will have better situational awareness and targeting capabilities than in previous years.
Western strikes against the Syrian regime in retaliation for the use of chemical weapons could affect Bashar al-Assad's military apparatus and push Russian Federation to return to the negotiating table, but also spark tensions in the region, according to experts.
The airbase is also known as the Khmeimim base and the news follows reports that President Bashar Al-Assad has fled to the same base.