U.S. President Donald Trump said, “we’re making a decision as to what we do with respect to the horrible attack that was made near Damascus…and it will be met forcefully.” 

U.S. President Donald Trump has threatened to take military action against Syria over a suspected chemical-weapons attack on civilians over the weekend, while Russia warned any such action would have “grave repercussions.”

Speaking at a meeting with U.S. military advisers late on April 9, Trump said, “we’re making a decision as to what we do with respect to the horrible attack that was made near Damascus…and it will be met forcefully.”

“We can’t let atrocities like we all witnessed…we can’t let that happen in our world…especially when we’re able to because of the power of the United States…we’re able to stop it.”

“We have a lot of options militarily, and we’ll be letting you know pretty soon. Probably after the fact,” Trump said.

The U.S. president later conferred with French President Emmanuel Macron, and they agreed on the need for a “firm response” to the attack, Macron’s office said.

Trump had earlier said that Syrian allies Russia and Iran may also bear some responsibility for the alleged chemical attack on April 7 in the rebel-held town of Douma, near Damascus, in which at least 40 people were reportedly killed.

“Everybody’s going to pay a price…. If it’s Russia, if it’s Syria, if it’s Iran, if it’s all of them together, we’ll figure it out,” Trump said.

Russia and Iran have given crucial military and diplomatic backing to Assad’s government throughout Syria’s seven-year conflict, which has killed hundreds of thousands of people and displaced millions.

The U.S. ambassador to the United Nations, Nikki Haley, urged joint action against Syria at a meeting of the UN Security Council on April 9, but vowed that the United States would act on its own if the UN didn’t respond.

“We have reached the moment when the world must see justice done,” Haley told the council.

Trump ordered missile strikes on a Syrian air base a year ago in response to a sarin-gas attack on the rebel-held town of Khan Sheikhun. Syria denied it was responsible for the attack, which killed at least 80 people.

At the time of the weekend attack in Douma, Syrian government forces and their allies were in the midst of clearing the last pocket of rebel resistance in the eastern Ghouta region, where the town is located. Russia announced on April 9 that it had resumed evacuating rebels and civilians from Douma under a negotiated pullout deal.

The threat of what could be imminent U.S. military action prompted Russian Ambassador to the UN Vasily Nebenzya to warn on April 9 that Moscow will not allow its forces on the ground in Syria to be put at risk.

“From what we hear now, I am afraid they are looking for a military option, which is very, very dangerous,” he said after the UN meeting, where he said Russia had investigated the scene in Douma and found no evidence that chemical weapons were used.

“There was no chemical-weapons attack,” Nebenzya said, adding that Syria and Russia had invited the international chemical-weapons watchdog to inspect the site.

“Through the relevant channels we already conveyed to the U.S. that armed force under mendacious pretext against Syria — where, at the request of the legitimate government of a country, Russian troops have been deployed — could lead to grave repercussions,” he said.

“Without any grounds and without thinking about the consequences, the governments of the U.S., the U.K., and France are pursuing a confrontational policy towards Russia and Syria and are pushing the others toward this,” Nebenzya was quoted as saying by Russian state-run news agency TASS.

The situation has “gone beyond the scope of what was acceptable even during the Cold War,” he said.

Staffan de Mistura, the UN special envoy on Syria, warned that the Syrian war has expanded beyond a national or regional conflict and is now a “threat to international security.” He said an escalation of the conflict could have “unimaginable consequences.”

Haley castigated Russia for backing Syria, saying that “Russia’s hands are covered in the blood of Syrian children.” She called Syrian President Bashar al-Assad a “monster” who “no civilized government would have anything to do with.”

Haley accused Russia of repeatedly allowing Assad to carry out “war crimes” against innocent civilians by vetoing UN efforts to hold him accountable.

The United States has repeatedly offered measures to establish an independent UN investigation of who is behind the chemical attacks in Syria. Haley offered another such resolution on April 9 and called for a council vote on April 10.

But Russia blocked several similar resolutions in the past, and Nebenzya hinted that the latest one — which he called “unacceptable” — would meet the same fate.

Haley accused Russia of protecting Syria at the UN while Moscow’s military advisers in Damascus are helping Assad wage a “starve or surrender campaign” against Syrian civilians that includes the use of chemical weapons.

“We are on the edge of a dangerous precipice,” she said. “The great evil of chemical-weapons use that once unified the world in opposition is on the verge of becoming the new normal. The international community must not let this happen.”

Earlier on April 9, the Kremlin said Russian President Vladimir Putin told German Chancellor Angela Merkel that “provocation and speculation” on the matter was unacceptable.

The UN’s top human rights official, Zeid Ra’ad al-Hussein, warned against what he called a “collective shrug” and “impotent” international response to the possible use of chemical weapons in Douma.

He said veto-wielding UN council members need to “wake up fast to the irreparable damage” being done to international efforts to ban such weapons of mass destruction.