Links have been alleged between the devices used in two 'toxic' attacks

The White House is working on plans to arm Syrian opposition forces for the first time, it was confirmed yesterday.

At the moment, the US is providing $250 million (£160 million) in defensive support — including body armour, night-vision goggles and food. But even while the US continues to pursue diplomatic moves to put pressure on the Assad regime, it has emerged that American firepower could be given to the Syrian opposition.

Caitlin Hayden, a National Security Council spokeswoman, said: “As the President has said, our assistance to the Syrian opposition has been on an upward trajectory, and he has directed his national security team to identify additional measures.”

A White House source confirmed it was reasonable to infer that those measures could include weapons.