A former king of Spain is preparing to stage an appeal after losing a High Court fight with an ex-lover.

Corinna Zu Sayn-Wittgenstein-Sayn, a Danish businesswoman, has taken legal action against Juan Carlos, who abdicated in 2014, and is seeking damages for personal injury.

She alleges he caused her “great mental pain” by spying on and harassing her.

Juan Carlos, 84, denies wrongdoing and disputes claims made against him.

Lawyers representing Juan Carlos argued that he was “entitled to immunity from the jurisdiction of the English courts in his capacity as a senior member of the Spanish royal family”.

But a High Court  judge disagreed.

Mr Justice Nicklin ruled earlier this year that the claim could go ahead in England.

Two Court of Appeal judges in July allowed Juan Carlos to challenge some of the conclusions reached by Mr Justice Nicklin.

Three appeal judges, Lady Justice King, Lady Justice Simler and Lord Justice Popplewell, are due to consider detailed arguments at a Court of Appeal hearing in London on Tuesday.

Lawyers representing Ms zu Sayn-Wittgenstein-Sayn have argued that the former king’s appeal bid should be dismissed.

Judges have heard how Juan Carlos ruled from 1975 until his abdication in June 2014 and the succession of his son King Felipe VI.

They have been told that Ms zu Sayn-Wittgenstein-Sayn, who lives in England and has a home in Shropshire, wants an “injunction and damages” resulting from “a continuous and ongoing campaign of harassment” against her, “commenced” by (the former king) from 2012, following the “break-up of an intimate romantic relationship” and her “refusal to let (the former king) use a financial sum irrevocably gifted to her, or to return other gifts”.

Lawyers representing her have alleged to judges that conduct “includes (the former king) or his agents smearing her and her business in the media, following her, entering her home in Shropshire, and bugging her homes and electronic devices”.

Mr Justice Nicklin rejected the argument that, despite his abdication, Juan Carlos remained a “sovereign” and was entitled to personal immunity under the State Immunity Act 1978.

He had also said Juan Carlos was not a member of the current king’s household within the meaning of that act.

Mr Justice Nicklin said the former king’s position under the Spanish constitution was “entirely honorary” and provided him “no continuing role”.