The Arab League said on Tuesday that those behind the chemical attack in Syria should face international justice.

In a statement issued after a meeting in Cairo, the 22-member organization said it held the Syrian government, led by President Bashar Al-Assad, fully responsible for last week’s gas attack in which hundreds were killed.

The League said it “demands that all the perpetrators of this heinous crime be presented for international trials,” reported Reuters.

It also urged the United Nations Security Council to “overcome the differences among its members by taking the necessary … resolutions against the perpetrators of this crime, for which the Syrian regime bears responsibility, and to end the violations and crimes of genocide that the Syrian regime has been carrying out for over two years.”

The Security Council has failed to take action against Syria, mostly because Assad’s close allies, Russia and China, have vetoed several Security Council resolutions condemning the Assad regime. The most recent such incident occurred after last week’s chemical attack, when the two countries forced the Security Council to simply say it was necessary to “clarify” the attack.

The Arab League’s statement came amid growing signs that the United States and its Western allies are preparing a strike to punish Syria for the poison gas attack in the suburbs of Damascus.

British Foreign Secretary William Hague said on Monday that the West could act even without full Security Council backing. Turkish Foreign Minister Ahmet Davutoglu similarly implied that his country was prepared to act without UN backing as well.