Video report by ITV News Political Correspondent Paul Brand

Britain could join the United States and take military action against the Syrian regime if it is asked to do so, the Boris Johnson has suggested.

The Foreign Secretary said it would be "very difficult to say no" if Donald Trump's administration asks the UK for help in tackling Bashar Assad's regime in response to another chemical attack.

He said the Government may bypass a House of Commons vote to authorise it.

Earlier this month, dozens of people were killed in a sarin gas attack on a rebel-held area in Idlib province.

The US launched a cruise missile strike on a Syrian regime air base as a direct response to the attack.

Speaking to ITV News, Mr Johnson said: "If the United States were to come to us with a request that we thought was reasonable and proportionate and measured for assistance then obviously we would have to consider that request."

As for whether it would be put to a vote in parliament, he added: "We'd have to consider it one way or another. Given our very, very close strategic relationship with the US I think we would find it very difficult to say no."

Liberal Democrat leader Tim Farron said it was "critical" for ministers to obtain Parliament's consent before taking action, and warned Mrs May not to do so under cover of the election period, when there were no MPs in place.

Lib Dem leader Tim Farron says the government needs parliament's consent before taking action. Credit: PA

Labour leader Jeremy Corbyn said the government should focus on securing a political settlement in Syria, rather than taking unilateral action.

There is no legal requirement on the government to seek parliamentary approval before ordering military action but it has become convention to consult MPs, except in the event of an emergency, according to the House of Commons library.

Downing Street said: "The US have been clear that they are not planning any further strikes, but they could reconsider if the Syrian regime uses chemical weapons again and anything beyond that is hypothetical."