Cheddar Man is a reminder that Britain has been home to migrants "for a lot longer than we think", the leader of a migrant solidarity campaign said.

Matt Carr, founder of One Day Without Us in support of migrants in the UK, said the fact that the first modern Briton had dark skin challenges "extreme right-wing" ideas about British origins.

It comes as scientists revealed earlier this month that the historical figure, who lived 10,000 years ago, had "dark to black skin", dark curly hair and blue eyes - a departure from previous conceptions of early modern Britons as lighter-skinned.

Mr Carr said the finding could add an "interesting ingredient" to the debate about "indigenous people", a discourse which he called one of the "defining components" of Brexit.

One Day Without Us will host a "national day of action" in solidarity with migrants on Saturday, in which towns and cities across the UK will host demonstrations and observe a "moment of unity" at 2pm.

Mr Carr told the Press Association: "One of the defining components of Brexit... there's this belief... that sometimes drifts dangerously close towards the mainstream, that taking the country back means taking the country back for white people.

"You'll hear references to 'our indigenous people'. It's extreme right-wing discourse that basically means white people. So it's quite interesting to see the Cheddar Man - it's a bit of a challenge for these narratives.

"Perhaps he can also remind us in the UK that we have been a country of migrants for a lot longer than we think."

Mr Carr launched the One Day Without Us campaign in 2016, and the first national day of action took place on February 20 last year, with the support of charities and unions including Unison and Unite.

The efforts, inspired by a similar protest in the US in 2006, sprung out of a Facebook conversation and, through word of mouth, garnered thousands of supporters - many of them immigrants - along with dozens of demonstrations, rallies and events nationwide.

He said of the movement: "Personally, I consider the campaign that we have one of various responses to the post-referendum climate - there will be others after us."

Campaigners will hold a rally in Parliament Square over the weekend, and are calling on the British public and politicians to be "proud to stand with migrants" at a time Mr Carr called a "social emergency".

Mr Carr, also an author, said the Brexit referendum "emboldened" racist and xenophobic attitudes "that we once believed were in decline".

He said: "We're asking people to show solidarity, and to be more vocal and forthright in defence of people who are under threat, and forthright about the UK as a country of migration, instead of always seeing migration as a problem."

He also voiced concerns that Government proposals to provide "settled status" to EU nationals who had lived in the UK continuously for at least five years before EU withdrawal, did not reassure those affected.

He said the NHS and construction were "key sectors" which relied on immigrants.

"The message we wanted to put out was 'proud to be a migrant, proud to stand with migrants'. We're going to try and challenge the use in British political discourse of migrants as a kind of pejorative (word)," Mr Carr said.

The One Day Without Us national day of action takes place on February 17.

Information about events can be found here: http://www.1daywithoutus.org/events-1daywithoutus-17-02/ By Isabel Togoh