Some social media users took aim at the former hypnotist, who supports abolishing the monarchy, for releasing his message at the same time as His Majesty.

Mr Polanski is set to talk about a three-day visit to Calais he made in the run-up to the festive period where he will say he witnessed French police, paid for by British taxpayers, slashing tents and confiscating wood used by sheltering migrants to keep warm.

The Green leader will say: “This has to stop – the constant political rhetoric and demonisation of people who are just trying to survive in unimaginable living conditions. I don’t believe we’re the country who the media paint us to be. I don’t believe that we’re cruel and heartless. And I don’t believe that if people saw what I’ve seen in recent days, they would turn away.”

He will add: “We should be diverting that money to a humanitarian and compassionate response. The rhetoric we hear about ‘stopping the boats’ and ‘smashing the gangs’ – none of this is working.”

Acknowledging his “unusual” Christmas message, he will also call for donations to the Calais Appeal, a group of organisations working to support migrants in the vicinity of the port.

His message comes as debate has ramped up this year around the UK’s membership of the European Convention on Human Rights (ECHR) in relation to immigration cases in the UK.

Both the Conservatives and Reform UK have said they would quit the convention in an effort to tackle immigration.

More than 41,000 people having now crossed the English Channel in small boats this year.