As international outrage over the Syrian regime’s latest chemical attack mounts, US President Donald Trump vowed on Monday that “major decisions” would be taken over the latest development. The United Nations Security Council held an emergency meeting on Monday to tackle the attack that left dozens dead on Saturday in Douma in Eastern Ghouta. The US also circulated a draft resolution for a new independent inquiry of chemical weapons attacks in Syria. Trump condemned the "heinous attack on innocent" Syrians, as he opened a cabinet meeting at the White House, adding that decisions would come in the "next 24-48 hours". "This is about humanity -- it cant be allowed to happen," he said. “The images, especially of suffering children, have shocked the conscience of the entire civilized world,” White House spokesman Sarah Sanders said. “Sadly, these actions are consistent with Assad’s established pattern of chemical weapons use.” The Syrian regime and its ally Russia have rejected claims of a chemical attack, with President Vladimir Putin warning against any "provocation and speculation on this matter". Trump -- who last year launched a missile strike on a regime air base after another alleged chemical attack -- warned Sunday that there would be a "big price to pay". US Defense Secretary Jim Mattis said Washington does not "rule out anything", while Trump and his French counterpart Emmanuel Macron vowed a "strong, joint response". With tensions high, deadly missile strikes on a regime airbase early Monday raised the specter of Western military action, but Damascus and Moscow said Israel was responsible. Rescuers and medics in Douma say more than 40 people died after a poison gas attack late Saturday in Douma, the last rebel-held pocket of the one-time opposition stronghold of Eastern Ghouta. Access to the area, which has faced weeks of regime bombardment, is limited and there has been no way to independently verify the accounts. The attack killed at least 60 people had been killed and more than 1,000 injured in several sites in Douma, according to the Union of Medical Care Organizations (UOSSM), a Syrian aid organization. “The numbers keep rising as relief workers struggle to gain access to the subterranean areas where gas has entered and hundreds of families had sought refuge,” it said. One video shared by activists showed bodies of about a dozen children, women and men, some with foam at the mouth. The Organization for the Prohibition of Chemical Weapons, a UN watchdog, said it was investigating the allegations but that so far only a "preliminary analysis" had been carried out. At the UN, it said that the use of chemical weapons was not justified and that those behind it should be held accountable. The UN human rights chief lambasted Security Council members for offering only “feeble condemnations.” “A number of very powerful states are directly involved in the conflict in Syria, and yet they have completely failed to halt this ominous regression towards a chemical weapons free-for-all,” Zeid Ra’ad al-Hussein said in a statement. Russias Foreign Minister Sergei Lavrov said Russian experts from its military deployment on the ground in Syria had visited the site and "did not find any trace of chlorine or any other chemical substance used against civilians". It briefly appeared in the early hours of Monday that action had been taken, as Syrian state media reported missile strikes on an airbase, but blame later fell on Israel which has carried out repeated strikes on regime targets. Syrian regime forces have waged an assault since February 18 on Ghouta, that has killed more than 1,700 civilians and left opposition factions cornered in their last holdout of Douma, Ghoutas largest town.