Members of the European Parliament passed a non-legislative resolution Thursday by a show of hands condemning the "mass killing of civilians with chemical weapons" last month.
U.S. Secretary of State John Kerry said the Syrian government killed more than 1,000 civilians in an Aug. 21 attack using sarin gas on a Damascus suburb.
A statement published Thursday on the European Parliament's website said "the use of chemical weapons in Syria is a war crime and a crime against humanity which demands a clear, strong, targeted and united response, not excluding eventual deterrent measures."
British Foreign Secretary William Hague briefed members of the British Parliament on the government's reaction to chemical weapons use in Syria. He said there was "no doubt" the Syrian government of President Bashar Assad gave the order to use sarin on the civilian population.
Hague said Thursday the Syrian government had pledged to cooperate, open its sites to inspectors, sign the Chemical Weapons Convention and gives up its chemical arsenal.
"If the Syrian regime verifiably gave up its chemical weapons stockpiles this would obviously be a major step forward," he said. "We agree with President [Barack] Obama that this initiative has the potential to remove the threat of chemical weapons without the use of force."