Harry, King Charles' younger son, sued publisher Associated Newspapers last year over a February 2022 article alleged he offered to pay for police protection only after bringing a separate legal fight against the British government.
The report also accused Harry, 39, of attempting to mislead the public about his willingness to pay for the policing, which was withdrawn after he stepped back from royal duties in 2020.
Harry applied to have the newspaper group's defence thrown out, with his lawyers arguing in March that Harry first offered to pay for police protection at a crisis meeting with the late Queen Elizabeth, his father and brother Prince William at the royal Sandringham estate in January 2020.
Associated's lawyers, however, said the publisher had a strong defence and argued that a statement issued by Harry's representatives before Associated's article was published had falsely claimed the government had refused Harry's offer to pay for police protection.
Judge Matthew Nicklin said in a written ruling that Associated's defence had a real prospect of success at trial, which he said was likely to take place in 2024.
The judge added that Associated is "entitled to seek to prove, as a fact, that (Harry) had not made an offer to pay for his state security to the government" before he brought his separate legal challenge.
Nicklin also said Associated had a real prospect of showing at trial that statements issued on Harry's behalf about his case against the government were misleading.
Friday's decision comes a day after Harry's legal challenge against the government's decision to withdraw his police protection, which his lawyers argue is unfair, concluded.
A ruling in that case is not expected until a later date.
