Two investigations into former Spanish King Juan Carlos' business dealings failed to find adequate evidence of criminal activity, Spain's national prosecutor's office announced Wednesday.

Juan Carlos, 84, who left Spain for the United Arab Emirates (UAE) under a cloud of scandal in August 2020, has been the subject of multiple money laundering investigations by Spanish and Swiss authorities for the past two years.

Spain's decision to close the two probes, linked to payments allegedly received over a high-speed train contract in Saudi Arabia and an offshore account in Jersey, follows a similar move by Swiss prosecutors last December.

In a statement, the prosecutor said it had been unable to demonstrate any link between a 65 million euro ($72 million) payment received by the former king and the awarding of the lucrative Saudi rail contract to a consortium of Spanish companies.

Even if the prosecutor could prove any wrongdoing, the activities would fall outside of a statute of limitations and Juan Carlos would have had constitutional immunity as a monarch at the time, it said.

Juan Carlos has paid around 5.1 million euros in back taxes as a result of the investigation, the prosecutor added.

The former king's lawyer said the prosecutor had failed to prove the existence of any wrongdoing or criminal behavior.

Juan Carlos came to the throne in 1975 after the death of General Francisco Franco and was widely respected for his role in helping guide Spain from dictatorship to democracy.

But his popularity sank in later years due to a series of scandals, prompting him to step down in 2014.