The hard–right Restore Britain party descended into open warfare today, as one of its most prominent backers said it has 'served its purpose'.The party's anti–immigration fan base reacted with outrage after an interview clip emerged of its leader, Rupert Lowe, defending multiculturalism.The Great Yarmouth MP was seen defending the King's invitation of Muslim worshippers to Windsor, adding: 'He's certainly very keen to propagate a multicultural society, which again I have no problem with if people integrate.'The statement sparked immediate backlash, with prominent supporter and activist Connor Tomlinson blasting: 'Multiculturalism has not worked, will never work, and was never wanted'.He added: 'If Restore Britain amounts to nothing more than a pressure campaign, then it has served its purpose.'Mr Tomlinson also went public to condemn the party's 'Structural problems, weak candidates, and blasé decision–making', which he warned has 'stalled, possibly squandered' the opportunity to overtake Reform UK as the party of the right.Steve Laws, a far–right supporter of Restore Britain who said Jews should be deported en masse from Britain, joined the chorus of outrage as he demanded an immediate apology from Mr Lowe for his comments.Laws set out other steps he wants to see, including a commitment to 'remigration' – the mass deportation of foreigners from the country – adding: 'That's the bare minimum we expect from [Lowe]. If he won't do it, then we'll need a new vehicle.' Rupert Lowe was blasted by supporters of his hard–right party Mr Lowe defended the King's support of Islam, adding he has 'no problem' with a multicultural societyAnother prominent member of the party with 43,000 followers on X fumed: 'I'm not voting for multiculturalism. If you share the same worldview as Zack Polanski, what's the point?'As well as today's online furore about multiculturalism, a prominent donor of the party, who goes by the name of 'Lord Miles' on X, also vented fury at his treatment by the party.Miles Routledge, who gave £2,500 to Restore, said he had been promised 'a simple thank you call' from Mr Lowe, which had 'never happened'.He also attempted to sign up as a candidate for the local elections, but never heard back. He suggested that his treatment by the party was now making him question whether to follow through with plans to 'donate substantially more'.The online squabbling prompted delight within Reform UK, which has repeatedly warned that Restore risks splitting the vote and handing Britain over to a hard–left government at the next election. Far–right supporter Steve Laws demanded an apology from Mr Lowe while threatening to jump ship A Reform UK source delighted in the chaos, pointing to Nigel Farage's longstanding criticism of multiculturalismA source told the Mail: 'Restore are already tearing themselves apart as they've found out what we already knew.'Rupert is a Tory to his core, Nigel has been calling out multiculturalism for over a decade –'Rupert should do everyone a favour and join the Tories already.'Mr Farage said as far back as 2011 that multiculturalism 'isn't working', a message he has repeated since.Restore Britain won shy of 7% in the Makerfield by–election, its first major outing as a political party.While the party celebrated retaining its deposit – alongside just Labour and Reform – it fell well short of expectations within the party.Days before voters went to the polls, one senior source told the Mail that they were aiming for between 15 and 20% on the day, while Mr Lowe said at the count he would be delighted with 10%.Restore also won fewer votes than the BNP managed in Makerfield at the 2010 general election.Restore was approached for comment.