A Saudi billionaire applied to become a diplomat in a "spurious" bid to claim diplomatic immunity and defeat his ex-wife's financial claim against him in the UK, a High Court judge has ruled.

Christina Estrada, a former Pirelli calendar girl, is seeking a multimillion-pound share of Sheikh Walid Juffali's estimated £4 billion fortune after 13 years of marriage and the birth of a daughter, now aged 13.

D r Juffali argued he had already provided the London-based former supermodel with a "generous" settlement, and his diplomatic status shielded him from any financial claim in the courts.

The 60-year-old international businessman believed he had acquired diplomatic immunity when he was appointed a permanent representative to the International Maritime Organisation (IMO) by the Caribbean island of Saint Lucia in April 2014.

But Mr Justice Hayden, sitting in the High Court family division in London, ruled his appointment was "an entirely artificial construct" - and marked the second time he had sought to avoid the English divorce courts.

The judge said it was legitimate to observe that Dr Juffali had gone to "considerable lengths in the divorce of his first wife, who also lived in the UK with their children, to avoid the jurisdiction of the English court."

The judge added: "I am satisfied that a similar motivation to avoid the jurisdiction of this court is the driving force behind (Dr Juffali) seeking the IMO appointment."

The judge also found Dr Juffali was liable to face the courts because of his residence in the UK, where he owns several luxury properties.

Dr Juffali's spokesman Michael Farrant said later the tycoon was proud to serve as St Lucia's permanent representative to the IMO and the judge's ruling would be appealed in the Court of Appeal.

Mr Farrant said the judge's comments were "deeply offensive" and his findings set "a dangerous precedent for diplomats everywhere".

Mr Farrant added: "He (Dr Juffali) does not believe that the English justice system has performed its duties in an appropriate manner in this case, nor that an English judge has the capacity or right to intrude on matters relating to the diplomatic arrangements and/or appointments of another state.

"In addition, Dr Juffali has been surprised and disappointed by the calculated misinformation campaign that wrongly asserts that he does not and has not provided generous financial support to his family. He has done and continues to do so."

Ms Estrada, 53, had argued her former husband's diplomatic status appeared to be "a flag of convenience" and the tycoon had never attended a meeting of the IMO since his appointment.

The former supermodel also gave evidence in court that he was seriously ill with cancer in a Swiss hospital unable to carry out diplomatic activity and his diplomatic status was a "contrivance" to defeat her case.

Rejecting the ex-husband's application to strike out her financial claim, the judge declared: "I am satisfied that what has transpired here is that (Dr Juffali) has sought and obtained a diplomatic appointment with the sole intention of defeating (Ms Estrada's) claims consequent on the breakdown of their marriage.

"Dr Juffali has not, in any real sense, taken up his appointment, nor has he discharged any responsibilities in connection with it. It is an entirely artificial construct."

Frances Hughes, senior partner of law firm Hughes Fowler Carruthers, who represented the ex-wife, welcomed the ruling.

Ms Hughes said: "Mr Justice Hayden has found that Dr Juffali sought diplomatic immunity with the sole intention of defeating my client's claims.

"The issue of diplomatic immunity is one with profound international importance, and my client is grateful to the judge for his clear findings in her case.

"Nevertheless, all my client seeks is an appropriate and fair settlement of herself and the parties' daughter."

Dr Juffali divorced Ms Estrada in Saudi Arabia but asserts in court statements that he has made "generous" provision and acquired for her a property in Beverly Hills, California.

He says he already pays Ms Estrada 100,000 US dollars (£70,700) per month and meets all the expenses of their 13-year-old daughter and intends to make further provision for her "at the appropriate time".

Ms Estrada says Dr Juffali obtained the divorce without her knowledge and it is not possible for her to bring any financial claims against him in his Saudi homeland.

According to papers before the court, London-based Ms Estrada's claim, if successful, could potentially be worth "many millions of pounds". She has said she is "unsure" of the legal ownership of the Beverly Hills property.

She obtained leave under Part III of the Matrimonial and Family Proceedings Act 1984, which relates to overseas divorces, to make an application for financial relief in the family courts in London.

Ms Estrada's legal team argued that any immunity he did have was limited to his official, diplomatic functions and did not extend to the family court proceedings because he is "a permanent resident" of the UK with strong and enduring ties to the country, including those with his ex-wife and his daughter, who was born in England.

Her lawyers submitted Dr Juffali had acquired from his mother Bishopsgate House, a 10-bedroom property set in 40 acres adjoining Windsor Great Park which was the matrimonial home and valued in the region of £100 million.

He had also acquired a £41 million property in Walton Place, Kensington and Chelsea, south-west London, and a substantial property in Devon.

Although the properties were now subject to trust and corporate structures, they were clear indications of his very close ties to England.

Dr Juffali's legal team argued that he had substantial property elsewhere, including in Jeddah, Saudi Arabia, and did not permanently reside in the UK.

They also contended he enjoyed "general immunity" from being sued in the UK courts, including by his ex-wife, under Article 15 of the International Maritime Organisation (Immunities and Privileges) Order 2015.

But the judge rejected Dr Juffali's arguments.