Downing Street has said the Cabinet agreed the use of chemical weapons in Syria must not go "unchallenged" but gave no immediate details of UK involvement in any military action against the regime of Bashar Assad.

Following a two-hour emergency meeting summoned by Theresa May, No 10 said ministers had agreed Assad had a "track record" of using chemical weapons and that it was "highly likely" he was responsible for the attack on the rebel-held town of Douma on Saturday.

READ MORE: Donald Trump seems to soften tone over threat to attack Syria with missiles

A No 10 statement said: "The Prime Minister said it was a shocking and barbaric act which killed up to 75 people, including children, in the most appalling and inhumane way.

"Cabinet agreed that the Assad regime has a track record of the use of chemical weapons and it is highly likely that the regime is responsible for Saturday's attack.

"The Prime Minister said it was a further example of the erosion of international law in relation to the use of chemical weapons, which was deeply concerning to us all.“