The Trump administration on Friday defended its strikes against Syrian military targets overnight, while Russia and Syria slammed the attacks and warned they would provoke more terrorism and instability in the region.

From the United Nations to Capitol Hill to the Pentagon, U.S. officials said the attacks were justified in targeting the Shayrat air base that was used to launch a chemical weapons attack that killed scores of men, women and children in Syria’s Idlib province Tuesday.

“It is in our vital national interest to prevent the use and spread of chemical weapons,” Nikki Haley, the U.S. ambassador to the United Nations, told the U.N. Security Council during a special meeting on the strikes. She added that she had warned the council on Wednesday that the United States might act alone.

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“Assad did this because he thought he could get away with it,” Haley said of Syrian President Bashar al-Assad. “He thought he could get away with it because he knew Russia would have his back. That changed last night.”





But Russia condemned the strikes against its ally in Damascus and said it was suspending an agreement to minimize the risk of in-flight incidents between U.S. and Russian aircraft operating over Syria.

President Vladi­mir Putin’s spokesman said the risk of confrontation between warplanes of the U.S.-led coalition and Russia in the skies over Syria has “significantly increased” after President Trump ordered the launch of 59 Tomahawk cruise missiles at Shayrat in retaliation for a chemical attack that killed more than 70 civilians.

U.S. military officials said they warned the Russians in advance that they were not the target of the missile attacks launched early Friday from the USS Ross and USS Porter, and that Russian forces did not attempt to use their advanced air-defense systems in Syria to stop the U.S. missiles.

The two countries have traded information about flights by a U.S.-led coalition targeting the Islamic State and Russian planes operating in Syria in support of the Assad government, to avoid accidents and misunderstandings, an effort known as “deconfliction.” The Russian Defense Ministry said Friday it was suspending the pact effective at midnight, because it sees the U.S. strike “as a grave violation of the memorandum.”

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U.S. military officials said they continued to communicate with the Russians before the deadline, including after the attack.

“There’s someone who is on the other end who is talking to us,” a senior U.S. military official said Friday.

(Sarah Parnass,Julio Negron/The Washington Post)

But the Kremlin’s decision to suspend the 2015 memorandum of understanding on the air operations immediately ratcheted up tensions further, even as Russian officials hoped the strike against Assad’s forces would not further sour U.S.-Russian relations already in a deep chill.

Secretary of State Rex Tillerson is scheduled to visit Moscow next week in what was to be an attempt to reset relations with Moscow and lay out U.S. positions on a variety of issues, including Ukraine and suspected attempts by Russia to meddle in the U.S. presidential election. Now, however, the prospects for the meeting have been overshadowed by the fallout from the strikes, which Russia’s U.N. envoy called an “illegitimate action by the United States.”

“The consequences of this for regional and international stability could be extremely serious,” Deputy Ambassador Vladimir Safronkov said during the U.N. Security Council debate.

“The U.S. has often talked about the need to combat international terrorism,” Safronkov added, yet it attacked the Syrian air force, which he claimed is leading that fight in Syria.

“It’s not difficult to imagine how much the spirits of terrorists have been raised by this action from the United States,” he said.

And Syria’s representative, Deputy Ambassador Mounzer Mounzer, called the United States and its allies, Britain and France, “the three colonialists” who, he said, pursue hypocritical ends in the Middle East.

The Russian government and some critics in the United States have questioned whether it is clear that the Syrians launched chemical weapons, rather than the suspected nerve agent being dispersed by other means such as a conventional bomb hitting a chemical storage facility on the ground. But U.S. military officials said they have high confidence that they know what happened.

“We know the routes that the aircraft took, and we know these aircraft were overhead at the time of the attack,” one senior U.S. military official said of the chemical weapons strike Tuesday.

The Pentagon released images Friday that it said showed the blast site where the Syrian bomb carrying a chemical weapon, likely sarin, detonated on Tuesday. Military officials said the staining on the road around the blast site crater is indicative of a chemical weapons attack. It was launched about 6:50 a.m., and a Russian-made aircraft piloted either by Syrians or Russians carried out an airstrike later in the day on a nearby hospital where many of the victims were taken for treatment, military officials said.

Senior U.S. military officials said they are investigating whether the Russian military participated in any recent chemical weapons strikes against civilians in Syria. But the officials said they do not yet have any information suggesting that the Russians did so.

The Syrian regime has increasingly faced pressure from opposition forces and was in danger of losing control of Hama air base in northwestern Syria, the officials said. The installation is believed to be used as both a base for Syrian helicopters and as a manufacturing facility for barrel bombs.

On March 25, a chlorine attack was launched in Hama, and a second chemical weapons attack of an undisclosed kind of gas was launched March 30, one senior U.S. military official said. That escalated to the attack Tuesday, in which the Syrians launched their largest chemical weapons attack since 2013, he said.

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“This escalatory pattern of using industrial chemicals, to using suspected chemical munitions, to verified chemical munitions, caused us obviously great concern about the direction this was going,” the official said.

In Congress, lawmakers called for a response to the chemical weapons attack that could include punitive measures against Russia, Assad’s chief sponsor in his war effort.

Senate Majority Leader Mitch McConnell (R-Ky.) suggested Friday that he would look favorably on a proposal to step up sanctions against Russia, Iran and others who support the Assad regime’s war effort in Syria — a measure that passed in the House last year but was never taken up in the Senate.

Putin has been supplying Assad’s army with warplanes and other reinforcements that the United States believes have been used in attacks on Syrian civilians.

But McConnell deferred to the Trump administration as to whether those sanctions would be necessary — unless bipartisan support for such a move in the Senate is considerable.

“If they [the administration] feel they need additional sanctions, or we can come up with something that seems to enjoy bipartisan support, I’d be open to it,” McConnell said. “The Russians are not out friend.”

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