More than 100,000 people have massed in central London for a march and rally organised by far-right activist Tommy Robinson, as anti-racism campaigners held a counter-protest.

Huge crowds, many draped in English and British flags, gathered through Saturday morning just south of Westminster for what Robinson, a veteran of UK far-right organising, has branded the country’s “biggest free speech festival”.

His latest “Unite the Kingdom” event saw attendees march over Westminster Bridge before rallying near Downing Street for speeches by far-right figures from across Europe and North America.

“The silent majority will be silent no longer,” Robinson told the crowd. “Today is the spark of a cultural revolution.”

UK police said an estimated 110,000 people attended, noting it used a combination of CCTV and police helicopter footage for its estimate.

Around 5,000 people attended a Stand Up to Racism march a mile or so to the north, as police deployed about 1,000 police to keep the rival groups apart.

The duelling demonstrations come amid growing anti-immigration sentiment, as protesters target hotels used to house asylum seekers.

Robinson, 42, who has a string of criminal convictions and a big online following after years of spearheading a fervent anti-Muslim and anti-migrant agenda, increasingly fuses those themes with claims that Britain is now hostile to free speech.

Far-right speakers