A former leading lawyer faces losing a £4 million London house in a court battle with a Saudi princess.

Ronald Gibbs, who worked as a partner for the “magic circle” law firm Linklaters, has been locked in “warfare” with Saudi royals after agreeing to set up and manage a $25 million (£19.7 million) investment fund for Princess Deema Bint Sultan Bin Abdulaziz Al Saud in 2011.

He bought shares for the princess in a boat-building company he controlled, a multi-million pound apartment in Montenegro and a £17-million, 40-metre superyacht.

But the princess and her brother, Prince Khalid Bin Sultan bin Abdulaziz Al Saud, complained that he failed to liquidate the assets and return the princess’s millions after being first asked to do so in 2013.

Mr Gibbs’s £4 million house on Kings Road in Richmond, west London, that he bought for his family in 2012, is now at the centre of the long-running legal battle.

Princess Deema, who is suing him at the High Court in London, is seeking an order for sale of the house to satisfy a £2.2 million interim damages and costs order that he owes.

But the former lawyer is resisting, claiming most of the beneficial interest in the house is owned by his former wife and children.

Mr Gibbs, an asset finance lawyer who became a partner at Linklaters, one of the top five London commercial legal firms, agreed to manage the £19.7 million investment pot handed to the princess by her father, former Saudi defence minister Sultan bin Abdulaziz.

The money was ultimately invested in an apartment at the Regent Hotel in Porto, Montenegro, superyacht company Silver Arrows Marine Limited and a Sunseeker 131 superyacht named Elysium.

Simon Atrill KC, representing the princess, said Mr Gibbs had in 2018 agreed to liquidate the investment portfolio by selling the assets, but by 2021 he had not complied.

This led to the princess suing him for breach of the 2018 agreement, the High Court heard.

After the summary judgment was entered against him for breach of the agreement, he was ordered to pay £582,077.49 interim damages and £1.64 million costs to the princess and her lawyers.

Mr Atrill told John Linwood, the High Court judge, that Mr Gibbs has “never repaid a penny” of the money despite “accepting his obligation to do so ... and having the means to do so”.

In relation to the house at the centre of the claim, the barrister continued: “In 2021, Mr Gibbs said – including by way of sworn affidavit and through his solicitors – that he owned the property 100 per cent beneficially. Mr Gibbs, an experienced solicitor, now seeks to deny that this is what he really meant.”

Mr Atrill said Mr Gibbs claims that when the house was purchased in 2012, he granted a 50 per cent beneficial interest to Sandra Gibbs, his former wife from whom he separated in 2006, and a 25 per cent beneficial interest to their three children.

Mr Gibbs and his former wife are representing themselves at trial. Mrs Gibbs told the judge she “can’t find the original trust deed, but have provided certified copies”, while Mr Gibbs asked the court not to expect him to have “legal superpowers” because of his former job.

In the hearing earlier this year, Mr Gibbs had claimed the costs and damages orders would ruin him, saying: “This is warfare against me.”

The claims were disputed by Mr Atrill. Judgment was reserved.