The three countries had carried out a wave of pre-dawn missile strikes, hitting targets near Damascus and in Homs province, Western officials said.
The US and its allies believe the Syrian regime was behind the attack, but Russia has long insisted it was staged by rebels in an attempt to provoke further Western intervention.
The Cabinet agreed on the need to take action to alleviate humanitarian distress and to deter the further use of chemical weapons by the Assad regime.
The OPCW decided to dispatch a fact-finding mission to the town after reports that more than 40 people died from exposure to toxic gas at the weekend.
Erdogan said he is extremely worried that some countries confident of their military power are turning Syria into a scene for arm wrestling.
Trump said that Xi responded on the Syria air attack saying "anybody that was so brutal and uses gases to do that to young children and babies" was okay to be struck at.