The Spanish royal family has denied that the country's former king Juan Carlos, 83, is "seriously ill" after rumours emerged in the media earlier on Monday.
The Royal House said that former king is in good health.
"I do gymnastics two hours every day and I feel fine," Hola! magazine quoted Juan Carlos as saying.
Pilar Eyre, an author and Spanish royal family expert, tweeted that Juan Carlos "is in serious condition" and may be transferred back to Spain from Abu Dhabi, where he currently lives.
"King Juan Carlos is in serious condition and the Royal House is evaluating the possibility of his transfer to Spain. His daughters, Elena and Cristina, have been the only members of his family who have moved to Abu Dhabi at the moment."
Juan Carlos moved to the United Arab Emirates last year after Swiss prosecutors opened an investigation into bank accounts he had allegedly set up in tax havens. In all, he's facing three separate probes in his native Spain. He's been under investigation for his alleged role in a deal that earned a Spanish consortium a multibillion-dollar contract to build a high-speed railway in Saudi Arabia.
Investigators are also looking into the use of credit cards linked to foreign accounts after Juan Carlos abdicated the throne in 2014 and no longer had immunity as head of state. If proven, the allegations may constitute a money laundering offence and the former king could be prosecuted.