MOSCOW — As Secretary of State Rex Tillerson arrived here Tuesday with a demand that Moscow back away from the Syrian government, Russian Foreign Ministry officials said relations with the United States had reached their lowest point since the Cold War.

Following a U.S. missile strike on Syria last week, the Foreign Ministry said it was concerned that the Trump administration might be considering a similar blow against North Korea.

And even before Tillerson exited his plane in Moscow, Russian President Vladimir Putin told a news conference that the Kremlin has “information” that provocateurs are planning to plant chemical substances in suburban Damascus and blame it on Syrian authorities. He gave no further details on the claim.

He said the situation in Syria reminded him of events in Iraq before the United States invaded in 2003, an allusion to unfounded assertions of weapons of mass destruction that the George W. Bush administration used to justify the war. He also said Western countries divided over the election of President Trump were scapegoating Russia and Syria.

“We’ve seen all this before,” Putin said.

(Reuters)

And the Russian general staff has put the United States on notice, saying that another missile strike would be “unacceptable.”

Russia and Iran back the government of President Bashar al-Assad, while rebel factions supported by the West and its partners have been largely driven back by withering attacks, including the use of a suspected nerve agent on a rebel stronghold last week that left at least 70 people dead.

[The Russia-Iran bonds that Washington cannot seem to break]

Putin’s spokesman said it remained unclear whether the Russian leader would meet with Tillerson.

“I cannot confirm yet,” Dmitry Peskov told The Washington Post after the private Russian broadcaster RBC reported that they would meet Wednesday.

Before leaving Italy — where he met with “like-minded” allies in the Group of Seven major advanced economies and diplomats from largely Muslim nations — Tillerson told reporters that the United States is aiming for a negotiated end to six years of conflict in Syria and wants Russia’s help in ushering Assad out of office.

Claiming that Assad’s rule “is coming to an end,” Tillerson previewed his message to Foreign Minister Sergei Lavrov.

“We hope that the Russian government concludes that they have aligned themselves with an unreliable partner in Bashar al-Assad,” he said.

In what was in effect an ultimatum, he said Moscow must calculate the costs of remaining an ally of Assad, the Iranians and Lebanon’s Shiite militia Hezbollah.

“Is that a long-term alliance that serves Russia’s interests?” he told reporters. “Or would Russia prefer to realign with the United States, with other Western countries and Middle East countries that are seeking to resolve the Syrian crisis?”

[U.S.-Russia rifts were already widening before missile strike]

Russia has maintained that a Syrian government airstrike last week hit a factory where Syrian rebels were manufacturing chemical weapons in the northern Idlib province. After the U.S. missile strike, Peskov asserted that the Syrian government “has no chemical arms stockpiles. ”

Moscow says it fulfilled its part of a 2013 agreement mandating that Russia oversee the destruction of Assad’s chemical-weapons arsenal. On Monday, Russia’s general staff said two sites where chemical weapons might remain are in territory controlled by Syrian rebels.

But Tillerson told reporters that last week’s attack with a suspected nerve agent shows that Moscow either did not take its obligations seriously or was incompetent. In either case, he added, the distinction “doesn’t much matter to the dead.”

“We want to relieve the suffering of the Syrian people,” he said, and issued an ultimatum: “Russia can be a part of that future and play an important role. Or Russia can maintain its alliance with this group, which we believe is not going to serve Russia’s interests longer term.”

Tillerson’s visit has the potential to be an opportunity or another marker in the escalation of tensions between the two great powers.

In Washington, State Department spokesman Mark Toner rejected Russia’s suggestion that the poisonings were the result of a deliberate provocation or “false flag” operation intended to falsely incriminate the Assad government.

“It is crystal clear to us that this was carried out, and that this was carried out by the Syrian regime,” Toner said. “There was no false flag.”

Assad’s responsibility for the attack, Russia’s role in policing its ally and Assad’s political future will be discussed when Tillerson sees Lavrov on Wednesday, Toner said.

“If there is an invitation for him to meet with Putin, of course he’ll do so. I think that’s a decision for the Kremlin to make and to announce, and up until now, we’ve not seen such an offer extended,” Toner said.

Tillerson is uniquely qualified to deliver a stern warning to the Russians. When he was the chief executive of ExxonMobil, he negotiated a deal with the state-controlled gas company Rosneft, leading Putin to bestow the Order of Friendship on him. Tillerson gained a reputation as being willing to walk out on energy deals that did not meet his standards.

[What is the Russian Order of Friendship, and why does Rex Tillerson have one?]

Diplomats at the meeting in Italy did not agree on a British proposal to impose more sanctions on Russia over Syria, on top of sanctions already in place over Ukraine. Italian Foreign Minister Angelino Alfano said ministers want Russia to pressure Assad but warned, “We must not push Russia into a corner.”

Anne Gearan in Washington contributed to this report.

Read more:

Trump officials defend Syria strikes, say they were in ‘vital national interest’

Timeline of the U.S. strike against Syria: How did we get here?

With the U.S. and North Korea saber rattling, is conflict imminent?

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