Spain's former king Juan Carlos I on Monday won permission to appeal against a London court ruling that allowed his former lover to bring a harassment case against him.

Corinna zu Sayn-Wittgenstein-Sayn, 58, is seeking civil personal injury damages from the 84-year-old monarch, who lives in the United Arab Emirates.

In March, a High Court judge rejected Juan Carlos' claim that he had state immunity and that English courts had no jurisdiction to hear the case.

Judge Matthew Nicklin ruled that he was no longer a member of the royal household of his son, the current Spanish King Felipe VI, that would give him legal protection.

But two judges at the Court of Appeal have now allowed him to appeal. The case was adjourned without a date for a full hearing being set.

Zu Sayn-Wittgenstein-Say alleges that Juan Carlos harassed her after their relationship turned sour, using threats, break-ins at her properties and surveillance.

Lawyers for the Danish businesswoman accuse him of trying to frustrate her claim.

Juan Carlos, who appeared in court documents under his full name Juan Carlos Alfonso Victor Maria De Borbon y Borbon, strenuously denies the allegations.