Thousands descend on Trafalgar Square for free screening of Oscar-nominated film The Salesman in Trump protest

Thousands of people descended on Trafalgar Square for a free screening of an Oscar-nominated film just hours before Sunday’s star-studded ceremony in California.

The Salesman is up for best foreign language film but its Iranian director is boycotting the event over Donald Trump’s travel ban, which bars people from seven Muslim-majority countries entering America.

Asghar Farhadi’s film was given its UK premiere in the central London Square and received the backing of mayor Sadiq Khan as well as actors including Keira Knightley, Dominic West and Lily Cole.

Trafalgar Square was turned into a huge outdoor cinema for the screening, complete with food and drink stands.

Mr Khan took to the stage and, after a few microphone issues which prevented him being heard, declared to loud cheers: "President Trump can't silence me."

He said the "key message" they would send to the world by gathering together for the screening was that "London is open", and added that the city stands with Farhadi and "all those discriminated against because of their nationality, their faith or their background".

Mr Khan added he was "really proud" of the "fantastic audience" who turned up to watch the film, despite the grey clouds, the odd drop of rain and chilly temperature.

"There are people here from Iran to Iraq, from Shoreditch and Streatham, from Lebanon and London - showing the world that London is open. Open to talent, open to creativity and open to people," Mr Khan added.

"At a time when people want to have travel bans, we should talk about welcoming people. At a time when people want to build walls, we should build bridges.”

The director was not present at the premiere, held hours before the 89th Academy Awards in Los Angeles, but addressed the crowd in a recorded message.

Farhadi said: "Despite our different religions, cultures and nationalities, we are all citizens of the world."

He apologised for not being at the event in person, and added: "However, I am there in spirit and I thank you all from the bottom of my heart."

Actor Lily Cole also delivered a speech to the large crowd of people who had packed out the area in front of the National Gallery.

She said: "We are here to say what alternatives are possible, we are here to demonstrate that alternatives are possible and why things like the Trump ban are unnecessary in this day and age, because London is wonderfully open.

"I hope you remember the pretext that brought us here, because we may see more ludicrous policies coming out, we may see more attempts to discriminate against millions of people based purely on their race and where they were born.

"And what we all need to be here today to remember and keep saying is, 'no, that's not acceptable' and an alternative is possible."

This year's Oscars ceremony is expected to be dominated by political speeches about Mr Trump and his controversial travel ban, while comedian Jimmy Kimmel, who will host the show, has said the US president will be a target for jibes.