White House says Russia increasingly isolated over Syria

U.S. President Donald Trump's spokesperson on Tuesday increased pressure on Russia over last week's chemical weapons attack in Syria, calling Moscow isolated and saying it was trying to shift blame away from Syrian President Bashar al-Assad.

"Russia is on an island when it comes to its support of Syria," White House spokesperson Sean Spicer told reporters.

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Earlier Tuesday,U.S. Secretary of State RexTillersonissued an ultimatum to Russia: Side with the U.S. and like-minded countries on Syria, or embrace Iran, militant groupHezbollahand the embattled Assad.

Tillersonarrived in Moscow on Tuesday.It wasn't clear what the punishment would be for a Russian government that has used its military might to helpAssadand his allies score a series of battlefield successes in their war with Syrian opposition groups.

The nerve gas attack, which killed an estimated 87 people, many of them children, and Russia's allegation that rebels, and not Damascus, were responsible have chilled U.S. relations with Moscow after a presidential campaign during which Trump frequently called for an alliance with Russia to fight ISIS militants in Syria and Iraq.

The attack led the Trump administration to harden its attitude against Assad weeks after top U.S. officials said they were more concerned with defeating ISIS militants than getting Assad out of power.

The U.S. intelligence community has no consensus on whether Russia knew about the attack in advance, said senior White House officials, who briefed reporters on condition of anonymity.

Russia has defended the Syrian government, a staunch ally, against U.S. allegations it was behind the attack in Syria's Idlib province, saying there is no evidence to underpin those accusations. It has blamed Syrian rebels.

Planned 'provocations,' says Putin

Russian President Vladimir Putin showed that he wouldn't back down, saying Russia knew about planned "provocations" what he called fake chemical attacks to blame Syria's government for using chemical weapons.

It reminds me of the events in 2003 when U.S. envoys to the Security Council were demonstrating what they said were chemical weapons found in Iraq. We have seen it all already.- Russian President Vladimir Putin

He said the United Nations should first investigate the attack.

"It reminds me of the events in 2003 when U.S. envoys to the Security Council were demonstrating what they said were chemical weapons found in Iraq," Putin told reporters on Tuesday. "We have seen it all already."

Russia also announced Tuesday that it will host the foreign ministers of Iran and Syria on Friday.

But a White House official said there is no evidence to support Russia's claims that the attack was fabricated.

"The absolute mass of data we have in all the different vehicles we've gotten it it's just too massive for really any intelligence organization to fabricate in that short a period of time," the official said.

1st official trip to Russia

Tillerson's trip to Moscowis the first official trip to Russia by a member ofTrump's cabinet. It's unclear if Putin and Tillerson will meet.

Before heading to Russia, Tillerson told reporters that Moscow had either failed to take seriously its obligation to rid Syria of chemical weapons, or had been incompetent. But, he said, the distinction "doesn't much matter to the dead."

"We cannot let this happen again," he said.

"We want to relieve the suffering of the Syrian people. Russia can be a part of that future and play an important role," Tillerson added in remarks to reporters. "Or Russia can maintain its alliance with this group, which we believe is not going to serve Russia's interests longer term."

'The reign of the Assad family is coming to an end.' U.S. Secretary of State Rex Tillerson

Putinsaid Moscow would tolerate Western criticism of its role in Syria, but hoped that attitudes would eventually soften.

Meanwhile, a Turkish minister said test results confirm that saringas was used in the attack in Syria last week.

The international chemical weapons watchdog has scheduled a meeting of its executive council to discuss the use of chemical weapons in Syria.

According to a written notification posted Tuesday on the Organization for the Prohibition of Chemical Weapons' website, the behind-closed-doors meeting will be held Thursday at its headquarters in The Hague.

Tillerson said it was clear the U.S. saw no role for Assad in Syria's future, given that he had lost legitimacy.

"It is clear to all of us that the reign of the Assad family is coming to an end," he said. "But the question of how that ends and the transition itself could be very important in our view to the durability, the stability inside of a unified Syria."

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