Censor.NET reports citing Deutsche Welle.
"It is important that the UN and experts from the Organization for the Prohibition of Chemical Weapons gain immediate access and can carry out their investigation without hindrance," Gabriel told the German newspaper "Bild am Sonntag."
Gabriel said information Germany has received suggested state forces were behind the attack.
"We have information from our partners and from contacts on that ground that makes it very plausible that the Assad regime was behind this horrible poison gas attack," he said.
Watch more: Syria gas attack: Hundreds hospitalized with phosphorus poisoning. VIDEOS 18+
At least 80 civilians died in the air attack on the town in rebel-held Idlib province prompting an international outcry. The United States accuses the regime of President Bashar al-Assad of using chlorine gas mixed with a highly toxic sarin-like nerve agent in an air attack. UNICEF confirmed at least 27 children had been killed in the attack in Idlib.
On April 7, U.S. warships launched 59 Tomahawk cruise missiles at a Syrian government airbase following a chemical airstrike in the province of Idlib blamed on President Assad.
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