Boris Johnson, front-runner in the race to replace Theresa May as Britain's next prime minister, heard Wednesday he is to face a court hearing on claims he lied during the campaign in the run up to the 2016 Brexit referendum.

The papers presented to the court in London claim that Johnson repeatedly lied and misled the British public as to the cost of EU membership, expressly stating, endorsing or inferring that it was 350 million British pounds (441.9 million U.S. dollars) a week.

"The application is a (political) stunt. Its true purpose is not that it should succeed, but that it should be made at all. And made with as much public fanfare as the prosecution can engender," said Johnson's submission.

If convicted of charges of misconduct in public office, the former foreign secretary could be sent to prison.

District Judge Margot Coleman at Westminster Magistrates' Court in London announced Wednesday that a summons is to be issued against Johnson to appear before the court on a date yet to be announced.

If the Magistrates' Court at a preliminary hearing decides there is a case to answer, it will be referred to the higher Crown Court.

The case against Johnson has been brought by private prosecutor Marcus Ball -- a rare occurrence in British law.

Ball's lawyers presented papers to the court claiming Johnson had deliberately misled the public during the Brexit referendum campaign in 2016 and then repeated the statement during the 2017 snap general election called by Theresa May.

Johnson's supporters have described the case as a political stunt and an attack on free speech in Britain.

The judge said in her findings that the allegations made against Johnson are "unproven accusations," adding that "I do not make any findings of fact."