France persuaded President Donald Trump to stay in Syria and launch airstrikes as punishment for an alleged chemical-weapons attack, French President Emmanuel Macron claimed on Sunday.

Appearing live on French television station BFM, the 40-year-old leader said the US, Britain and France had "full international legitimacy to intervene" with the strikes, to enforce international humanitarian law.

He spoke as France joined forces again with the UK and the US to push for a peaceful path forward to the Syrian crisis, proposing a new United Nations-backed ceasefire.

The three allies have produced a draft resolution that will be debated by the Security Council in New York, although it remains unclear when the vote will take place.

Mr Macron tried to take credit for convincing Mr Trump to take a long-term view of Syria during pre-strike phone calls.