An anti-monarchy group has raised more than £10,000 in one day to fund billboards around the UK to call for an elected head of state and label Prince Charles as "wasteful".
Republic campaigns for an end to the current monarchy, which has been in place for some 1,000 years, calling for an "honest, grown-up" debate about the system.
Launching a crowdfunding campaign for billboards across the UK, the group stated: "With polls showing young people wanting an elected head of state, the succession of King Charles will be a major turning point in the monarchy's history and in the growth of Britain's republican movement.
"We want the country to know there is a positive, exciting, democratic alternative to sitting back and letting Charles become our head of state. And we want the country talking about why the monarchy is bad for Britain, why it's time to call time on the royals."
Republic wants £30,000 for the billboards, and is a third of the way there within a day of launching the campaign.
It comes as the Royal Family struggles with popularity levels, which Republic wants to capitalise on as the Queen approaches the end of her reign.
Polling from YouGov earlier this year showed a rise in the number of younger people, aged 18-24, who want to see the hereditary system replaced with an election for the role of head of state.
Support across the UK in general for an elected head of state had also gone up, but was still a minority view, with 24% backing it.
The Queen has always had high levels of personal support, but her son Charles has dwindled in popularity rankings for decades.
Prince William is often as popular as the Queen.
Republic added: "King Charles may inherit the throne, but he won't inherit the respect and deference enjoyed by his mother.
"The automatic succession of King Charles will dramatically alter the debate and public attitudes. Polling shows most people just aren't that interested in the royals and are divided on who should replace the Queen when she dies. We need to persuade them that there is a democratic alternative."
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Billboard creations shown on the crowdfunder include a large picture of Prince Andrew with the word "Wanted" next to him.
Underneath could read: "A democratic alternative to the monarchy."
Andrew, 61, stepped back from public duties in 2019 after a disastrous interview with BBC Newsnight about his friendship with sex trafficker Jeffrey Epstein.
The FBI has said it wants to speak to the Duke of York, but officers have said he has not co-operated with them. He accused them of seeking headlines not answers last year.
Andrew has been accused of having sex with Virginia Roberts Giuffre when she was trafficked by Epstein. He denies the allegation and no charges have been brought against him.
Other billboard designs feature Prince Charles, who will become king when his mother dies, with slogans including: "Secretive, wasteful, undemocratic. It's time to end the monarchy."
The Royal Family has had a difficult time over the last year and a half in particular as Prince Harry and Meghan made their shock announcement to step back from their senior royal duties.
In the last few months the Duke and Duchess of Sussex have opened the family and the systems around it up to more scrutiny, accusing someone within palace walls of racism when it came to the skin colour of their future children, and suggesting Meghan was left unaided when she was struggling with suicidal thoughts.
Prince Harry went on to suggest the way the Queen brought up Charles had a knock-on effect on his own childhood, which he said he sought therapy over.
Then came an incident involving Prince Michael of Kent, who does not carry out duties on behalf of the Queen, that saw him accused of being willing to use his royal status for personal profit and to seek favours from Russian President Vladimir Putin, in an undercover report by The Sunday Times.
However the Queen has been able to keep much of the resolve of these issues private for now.
After months of lockdown, the Queen has been keen to return to engagements in person, preferring to meet people face to face than over video calls.
As restrictions eased she has enjoyed Trooping the Colour, hosted US president Joe Biden, visited the G7 summit and made it to Scotland for her annual Royal Week.
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