An aristocrat accused of abusing Brexit campaigner Gina Miller online admitted he had been “foolhardy and unwise” but insisted he believed his Facebook posts were private.

Viscount Rhodri Colwyn Philipps, 50, faces trial next month for three messages posted in September and November, as Ms Miller fought for Parliament to have a say over triggering Britain’s departure from the European Union.

It is alleged Philipps, who lives in Knightsbridge and is the 4th Viscount St Davids, wrote: “£5,000 for the first person to ‘accidentally’ run over this bloody troublesome first-generation immigrant.” It is claimed he later added: “If this is what we should expect from immigrants, send them back to their stinking jungles.”

At Westminster magistrates’ court yesterday, Philipps suggested his prosecution was “politically motivated” and demanded to know why others accused of abusing Ms Miller were not in court.

He told Chief Magistrate Emma Arbuthnot: “I don’t pose a threat. What I wrote was perhaps foolhardy and unwise, but it was for a private group of people, not directed towards Ms Miller.

“The case against me is perhaps because of my name, because it’s newsworthy.”

It also emerged at the hearing that the aristocrat could face a further charge over an email sent recently to the police officer investigating him.

“It is a statement threatening his career through senior officers in the Metropolitan Police Service,” said prosecutor Kate Mulholland. “The Crown are considering witness intimidation charges in relation to this.”

Guyana-born mother-of-three Ms Miller, 52, spearheaded a successful court battle to force the Government to consult Parliament before triggering Article 50 to leave the EU. She was the target of abuse online during the battle at the Supreme Court. She is expected to give evidence at Philipps’s trial about the impact of his Facebook posts.

"Philipps applied to be able to cross-examine Ms Miller himself and, at other times during the fractious hearing, made accusations about her qualifications.

"He also interrupted the prosecutor repeatedly. Judge Arbuthnot ruled that a barrister would be appointed to question Ms Miller if Philipps was not legally represented at the trial, saying that the aristocrat’s tone was “hectoring”.

Philipps denied three charges of sending a menacing public communication, and is due to stand trial on July 10.