Thousands of people took to the streets of London on Sunday for the "Brexit Betrayal March" led by UKIP leader Gerard Batten and right-wing activist Tommy Robinson, with the Ruptly video news agency streaming the event live.
Addressing the protesters, Batter said that if the UK parliament fails "to take Britain out of the European Union, it will be the biggest constitutional crisis since the English Civil War."
He also branded the ruling UK political class as "treacherous and treasonous".
The event's Facebook page describes the march as a "democratic and peaceful demonstration expressing the strength of feeling amongst Leavers despite the torrent of anti-Brexit propaganda we have been exposed to for almost two and a half year."
The rally comes two days before the vote on the draft Brexit deal at the UK House of Commons. The agreement, promoted by Prime Minister Theresa May, has faced much criticism both from the opposition and the ruling party, with several members of the cabinet having resigned over disagreements with the deal.
Counter-protests have also been held in the UK capital earlier in the day.
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