A SERIOUS “grown-up” debate about the future of the monarchy must happen in the UK Parliament after a poll showed support has fallen below 50% for the first time, an MP has said.

The Savanta poll commissioned by Republic also showed one in five people “don’t know” whether they want the royal family or an elected head of state, suggesting many lack enthusiasm for the monarchy but equally don’t know what alternative there could be.

The same question was asked in a poll in November and that showed only 13% of people didn’t know what they wanted, suggesting ambivalence or apathy are on the rise.

SNP MP Tommy Sheppard said the results of the poll show a desperate need for a proper discussion on the royal family at Westminster, as he described the survey as “game-changing”.

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Tristan Gray, convener of Scottish anti-monarchy group Our Republic, added the number of don’t knows was “depressing” and must be “fixed” with wider discussions on the issue.

He also argued that because the nepotism and entitlement of the monarchy is "baked into" many aspects of British society, lots of people feel “powerless” in the debate and would rather not give an opinion.

Fewer than half in all age groups under the age of 55 prefer the royals to an elected head of state, the poll showed.

Sheppard (below) said: “This poll is a complete gamechanger and it really outlines that we need to have a serious debate in the UK Parliament and it needs to be brought into scope in terms of debates we have about an independent Scotland too.

“In the UK there is not a majority against the monarchy yet, but what is notable is the big growth in the number of people in the 'don’t know' category.

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“It’s clear Queen Elizabeth was able to deflect incoming criticism with her longevity, but that is not there anymore. People are questioning what an earth is going on when we are in a cost of living crisis.

“What it suggests is public opinion in transition and it is time for a grown up discussion. It’s starting to show how out of touch the UK Parliament is.

“There are a handful of us in Parliament who would raise our heads above the parapet and shout about it, but there is so much about the culture and protocols that prevents discussion on the monarchy.”

Republic CEO Graham Smith also said the results showed the UK desperately needed to discuss the future of the royal family and the country's head of state, particularly in light of Prince Andrew recently being mentioned in the Jeffrey Epstein files. 

The same poll carried out in November last year showed that 52% of the public supported the monarchy – meaning support has dropped by four points in a matter of weeks.

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Gray’s Our Republic organised a panel discussion at the end of last year on what Scotland could look like without a monarchy, which is the type of debate he feels is needed regularly.

He told The National: “It fits what our experiences were with the coronation [the proportion of don’t knows]. You had a small core of people turn up very excited about the coronation, a small core turning up to protest, and the vast majority paying no attention to it.

“A lot of those people will be don’t knows because they feel it’s just not relevant to their every day lives.

“We feel a real debate needs to happen.

“We think that the monarchy is actually relevant to people’s everyday lives because we see over and over again the sense of entitlement and nepotism that is built into the British state with ex-prime ministers being able to give personal doners positions in the Lords and have powers over our laws.

“That’s baked into our system because the monarchy sets that precedent and that’s a real impact of how the monarchy is relevant to everyone.”

The poll was carried out amid reports of Prince Andrew's involvement with paedophile financier and billionaire Epstein after the Duke of York was named in court documents published online.

But although this will have contributed partly to falling support for the monarchy, Gray insists the central reason for it is King Charles coming to the throne.

Gray said: “I think the root cause of the decline in popularity is Charles does not have the capability to fulfil the same role in British consciousness as his mum did.

“He is not someone people have grown up with their whole lives as the edifice of the British monarchy, he’s just some billionaire bloke who has strong opinions, who clearly has a bunch of public flaws that people know really well.

“If you look at the 18 to 24 age group, a third of people are supporting the monarchy. If you think in the 2040s, those people are going to be 40 years old. They will be the main block of voters.

“The monarchy is in an unsustainable situation.”