Anti-monarchists protest outside British parliament

STORY: Among those attending Tuesday's protest was the lawyer in question, 36-year-old Paul Powlesland, who said people need to separate the issue of mourning the Queen and the new king's succession, pointing out they were not protesting near any funeral or remembrance.

"We’re at the political centre of power, where the king came yesterday to say that he's the new king,. We're his subjects and we’re here to say (that) actually we disagree. We politely and very respectfully disagree with you. You're not my king.”

Powlesland, had posted on social media an altercation he had with an officer in Parliament Square on Monday, while reportedly holding up a blank piece of paper. He said the officer told him he risked being arrested if he went ahead and wrote "not my king" on it because "someone might be offended".

The clip went viral, with more than one million views on Twitter. Scotland Yard later issued a statement, saying: "The public absolutely have a right to protest," British media reported.

Holding a "not my king" sign at Tuesday's rally, Powlesland said it was "great to be able to do that and to stand here peacefully expressing my opinion and exercising a very ancient British right that I think we’re all entitled to."

Charles, 73, automatically became king of the United Kingdom and 14 other realms, following the death of Queen Elizabeth on Thursday (September 8).