"We strongly condemn the attack and we have the strong suspicion it was carried out by the regime, whose record on the use of chemical weapons is known by the worldwide community", the ministry in Ankara said.
Turkey denounced the chemical attack in Douma: "We strongly condemn the attack, and we have the strong suspicion it was carried out by the regime, whose record on the use of chemical weapons is known by the worldwide community", the Turkish foreign ministry said in a statement.
Saturday's alleged attack pushed the holdout rebels back to the negotiating table.
USA government sources said on Monday the administration had not yet conclusively determined whether the attack was carried out by Mr Assad's forces.
But key backer Iran came to Assad's defence, saying the allegations were a Western conspiracy and echoing Russia's warning against foreign military action.
Assad's forces renewed their assault on Douma, the last rebel-controlled town in Eastern Ghouta, on Friday after talks over an evacuation of Jaish al-Islam fighters broke down.
A suspected chemical attack in a rebel-held area of Syria over the weekend left at least 40 people dead, according to aid groups. Rescue workers in Syria reported finding at least 42 people dead in their homes from apparent suffocation, and antigovernment activists circulated videos of lifeless men, women and children sprawled out on floors and in stairwells, many with white foam coming from their mouths and nostrils.
He added: "These latest reports must urgently be investigated and the worldwide community must respond".
Image Iran's Hassan Rouhani Turkey's Tayyip Erdogan and Russia's Vladimir Putin met in Ankara
After delying his intervention in Syria, US Department of Defense stated: "We continue to monitor situation closely and support ongoing diplomatic efforts to make those who use chemical weapons, in Syria and wherever, accountable", Added.
- Russian Federation casts a veto at the UN Security Council preventing the renewal of the mandate for the Joint Investigative Mechanism. Yevgeny Serberennikov, from the defense committee at the Federation Council, told the RIA Novosti news agency that Russia is eager for the OPCW to "finally start carrying out the functions it was created for".
A joint inquiry by the United Nations and the Organization for the Prohibition of Chemical Weapons found that the Syrian government was responsible. He criticized Russian Federation for what he suggested was its failure to ensure the elimination of Syria's chemical weapons arsenal under terms of a 2013 agreement. 'We are in close touch with our allies following these latest reports.
Mr Trump branded Assad an "animal" in a series of posts on Twitter. President Trump tweeted that "President Putin, Russia and Iran are responsible for backing Animal Assad", referring to Syrian President Bashar al-Assad, and that there was a "big price to pay".
It leaves open the question of whether the United States president will opt for a "discrete punishment or a more ambitious and co-ordinated" response, says The Guardian's diplomatic editor Patrick Wintour.
"The evidence points towards yet another chemical attack by the regime".
A year ago, Washington had launched several dozens of Tomahawk cruise missiles at a Syrian airbase after a chemical attack in the town of Khan Sheikhoun in northern Syria killed several people.
The alleged chemical attack by Syrian forces in Idlib in 2017, which led to Trump's decision to launch a cruise missile strike against the government's Shayrat Airbase in Homs, came just after Trump had announced that regime change in Damascus was now off the table as a USA strategic objective.
The Answer Trump Needs in Syria
The U.S. also wants to avoid causing more civilian deaths "and do everything humanly possible to avoid that", Mattis said. May is also expected to speak directly to Trump at some point about the next steps to take against Syria.