Spanish prosecutors in London have questioned a former German mistress of former king Juan Carlos after she said he had received a commission on a contract in Saudi Arabia, judicial sources said.
In July 2018, two Spanish media outlets released recordings confirming Corinna Zu Sain Wittgenstein that Carlos received a commission while Spanish companies were awarded a contract to build a high-speed train between Mecca and Medina in 2011.
The recordings were made by the imprisoned Capt. Villarjo police, who had recorded a number of conversations with Spanish politicians or contractors without their knowledge.
Prosecutors from the Madrid Anti-Corruption Prosecutor on Thursday questioned the German businesswoman in the British capital - where she currently resides - as a witness, judicial sources said.
The prosecution decided at the end of last year to investigate whether there were sufficient elements to file a complaint of corruption in international commercial transactions.
According to judicial sources, the investigation is concerned with investors who may have paid commissions to the former king himself when he was head of state and thus enjoyed immunity.
"Our client was happy to testify voluntarily in London to convey accurately to the authorities what others have told her about the 'high-speed train' agreement," said Wittgenstein's defense agent Robin Rathmil.
"Serious accusations in the media on financial issues related to the honorary king have existed for decades. If there is a real intention to properly investigate the (high-speed train) agreement and other charges, it is up to the Spanish judicial system and Spain."
Carlos has already come under fire after a portrait in Abu Dhabi with Saudi Crown Prince Mohammed bin Salman, who is suspected of being directly responsible for the killing of journalist Jamal Khashoggi.
The picture, which was first put on the Saudi Foreign Ministry's Twitter account, was published in several Spanish newspapers, including the conservative daily El Mundo, which titled it "The Image of Shame".
Carlos, 80, has maintained close ties with the Saudi royal family, which helped Madrid win lucrative contracts in the country. After a series of scandals he abdicated in 2014 to his son Felipe VI, who tried to restore the reputation of the monarchy.