Foreign Secretary: Britain should intervene if Syria used chemical weapons on civilians

He added that the use of these illegal weapons in Syria cannot go “unpunished”. Boris Johnson spoke out after claims that Syrian forces unleashed chemical weapons on the besieged rebel enclave of eastern Ghouta near Damascus over the weekend. One child died and 13 others suffered breathing difficulties after a suspected chlorine gas attack.

Photographs showed three little children desperately trying to breathe after being caught in the attack. The world’s chemical weapons watchdog, the Organisation for the Prohibition of Chemical Weapons, has already begun an investigation into the claims.

Mr Johnson told BBC Radio 4’s Today show: “It’s very important to recognise there’s no military solution that we in the West can now impose.

“The people listening to us, listening to this programme in eastern Ghouta cannot get the idea that the West is going to intervene to change the odds dramatically in their favour.

“But what I think we need to ask ourselves as a country, and I think what we in the West need to ask ourselves, is can we allow the use of chemical weapons, the use of these illegal weapons to go unreprieved, unchecked, unpunished?

“And I don’t think that we can.” 

He added: “If there is incontrovertible evidence of the use of chemical weapons, verified [by the Organisation for the Prohibition of Chemical Weapons], if we know that it’s happened and we can demonstrate it, and if there is a proposal for action where the UK could be useful, then I think that we should seriously consider it.”

The West’s options are limited but could include air or cruise missile strikes against chemical weapons stockpiles or targeting bases which carried out the attacks.

Last April the US fired 59 cruise missiles at Syria’s Shayrat air base, claiming Syrian president Bashar al- Assad had used it to launch a sarin gas attack which killed 80 people including women and children.

The Syrian regime has been repeatedly accused of using chemical weapons during the eight-year civil war.

Syria and its Russian backers deny the claims and blame insurgents.

Mr Johnson spoke as a fragile five-hour truce ordered by Russia began.