Theresa May is struggling to justify her decision to join air strikes against Syria.

The British Prime Minister has been grilled by MPs over her decision to join Donald Trump's strikes against the Assad regime.

Her party and many Labour MPs are backing her call.

But UK correspondent Rod Liddle told Mike Hosking she's having a harder time convincing the British public.

"The stuff that you get from Boris Johnson and indeed from herself has not been very convincing so far. What was it meant to achieve? No one is very sure."

May told MPs she couldn't justify standing by, while Syrians were suffering, but Liddle says she hasn't explained how the air strikes helped.

"Quite what it was meant to achieve in Syria is another issue. Again, there are still some people who say it may not have made the situation in Syria any better than it already was."

LISTEN TO ROD LIDDLE TALK WITH MIKE HOSKING ABOVE