UK won't commit to Syria strikes without more evidence, May tells Macron and Trump

UK Prime Minister Theresa May has refused to commit British troops to military action against Syria's regime without further information on Saturday's chemical massacre in the opposition town of Douma.

During a telephone conversation with presidents Donald Trump of the US and Emmanuel Macron of France on Tuesday, May stopped short of blaming the Syrian regime directly for Saturday's chemical attack, which left at least 40 civilians dead.

She also refused to say whether the UK might take part in airstrikes on Syria, as Trump and Macron make the case for intervention in response to Saturday's massacre, The Times reported.

"They agreed that reports of a chemical weapons attack in Syria were utterly reprehensible and if confirmed, represented further evidence of the Assad regime’s appalling cruelty against its own people and total disregard for its legal obligations not to use these weapons," a read-out of the conversation of May, Trump and Macron read.

This contrasted with the more forceful language of the US and French presidents who appear ready for action.

Macron said that French forces could launch strikes on Syria's chemical facilities.

Trump is expected to make an announcement on whether the US will launch air raids against Damascus. Saudi Arabia and Qatar have said separately they could take part in military action, if asked.

US and French forces have reportedly moved to the eastern Mediterranean in anticipation of the strikes.

Civilian flights have been told to exercise caution in the area by a European flight control body.

May is said to be considering whether to call parliament - which is in recess - for a vote on military intervention on Syria strikes.

Some members of her party believe that parliament should have the final say on whether the UK takes part in the strikes. It is not clear whether a motion would pass a vote.