When Elon Musk asked his 211 million followers on X to vote on whether “America should free the people of Britain from their tyrannical government,” it seemed like the post might just be a joke.

But it comes after a series of scathing posts about Britain by Mr Musk – attacking the Labor prime minister, Keir Starmer; seeking release of the closed far right agitator; and broke with the leader of the hard right, Nigel Farage – came off less as a joke than as a move by a powerful man who revels in his ability to shake up the politics of another country.

Appearing on X over the holidays like unwanted guests at a Christmas party, Mr Musk’s posts thoroughly hijacked the political debate in Britain in early 2025.

On Monday Mr Starmer used press conference about framing the British National Health Service to deny the claims of Mr. He regrets not acting when he was Britain’s chief prosecutor more than a decade ago against gangs that sexually abused girls.

Mr Farage, for his part, faced questions about his future as leader of the right-wing anti-immigration Reform UK party after Mr Musk stated at X on Sunday that “Farage doesn’t have what it takes.” A day later, Mr Farage announced a call for a national inquiry into child sexual abuse, addressing one of Mr Musk’s favorite causes.

“Musk has a very skewed understanding of British politics and yet he has a megaphone,” said Robert Ford, a professor of politics at the University of Manchester. “When he says these things at 3am on a Sunday night, it disrupts the whole NHS Labor press conference on Monday.”

The long-term effect of Musk’s erratic crusade was harder to predict, Professor Ford said, but some of his moves could backfire. His break with Mr Farage, for example, could work to Mr Farage’s advantage.

The likely cause of the split was Mr Farage’s refusal to back Mr Musk’s demand to free the far-right agitator Tommy Robinson. Mr Robinson, whose real name is Stephen Yaxley-Lennon, is serving a prison sentence for defying a court order by repeating defamation against a young Syrian refugee. He has multiple criminal convictions and a record of racist and Islamophobic statements.

In Britain, Professor Ford said: “Tommy Robinson is political kryptonite. There’s a reason Farage wants nothing to do with him, and never has.”

By refusing Mr. Robinson defying Mr. Musk, he said, Mr. Farage could make himself more acceptable to majority voters on the right who are disillusioned with the Conservatives. Mr. Musk, he added, will also find that there are no clear alternatives for party leader Mr. Farage, the architect of Brexit and a fixture in right-wing British politics for decades who pushed Reform UK during last year’s election campaign.

For Mr Starmer, who has returned from a rare holiday that had to be postponed due to the death of his brother, Mr Musk’s intervention was another setback after an inauspicious start to his fledgling government. With his personal ratings falling in the polls, Mr. Starmer hoped to start by 2025 by delivering a plan to reduce patient waiting times in the NHS

Instead, reporters asked him about Mr Musk, who falsely claimed Mr Starmer covered up the abuse and exploitation of girls in the 2000s and 2010s by gang members, many of whom were of British-Pakistani descent. “Jail for Starmer,” Mr. Musk wrote in a post on Monday morning.

“It must have irritated him beyond words to have to deal with this sort of thing,” said Steven Fielding, emeritus professor of political history at the University of Nottingham. The Prime Minister, he said, was trying to avoid a “street fight” with Mr. Masculine and focus on ruling.

Mr Starmer noted that when he was director of the Crown Prosecution Service between 2008 and 2013, his office launched the first of several cases against a groom group and drafted guidelines for mandatory reporting of child sexual abuse. He tackled the scandal “head on,” he said.

The Prime Minister became visibly angry as he defended Jess Phillips, the Minister for Protection and Violence against Women and Girls, against Mr. She accused herself of being a “rape genocide apologist” for rejecting calls for a national inquiry into child sex exploitation in Oldham, a town near Manchester.

Ms Phillips instead asked for the Oldham authority to lead the inquiry, rather than central government. Mr Starmer said she had done “a thousand times more than they even dreamed of when it came to protecting victims of sexual abuse.”

Elizabeth Pearson, author of a book on the British far-right, Extreme Britain, said Mr Robinson, who was convicted of assault and fraud, had been lucky to attract “the attention of one of the most powerful men in the West. .”

She and other analysts are more confused about what Mr. Musk stands to gain from backing a reviled figure who has occupied the sometimes violent fringes of British politics. The number of X daily users in Britain has fallen since Mr Musk took over the platform formerly known as Twitter; Advocacy Mr. Robinson, experts said, is unlikely to reverse that trend.

“It is foreign interference in our system,” said dr. Pearson, Senior Lecturer at Royal Holloway, University of London. “At this point, I feel that Musk is becoming a bad actor who wants to destabilize our system.”

Professor Fielding said Mr Musk was probably pandering to his audience in the United States. The risk, he said, is that “anyone who is serious in the American administration will think that this man is creating fires that are absolutely unnecessary.”

Mr. Musk’s activism has caused alarm in other European countries, such as Germany, where he is based supported a far-right party with neo-Nazi ties. On Monday, French President Emmanuel Macron told a diplomatic audience: “Ten years ago, who would have imagined that the owner of one of the world’s largest social networks would support a new international reactionary movement.” He did not mention Mr. Musk by name.

Likewise, Mr. Starmer has shown no appetite to single out Mr. Musk, a close ally of President-elect Donald J. Trump, with whom Mr. Starmer and his aides have tried to cultivate a relationship. “This is not about America or Musk,” he told reporters on Monday. “I’m talking about our politics.”