Spanish prosecutors are investigating a possible diversion of public funds by a foundation once headed by Iñaki Urdangarin, who is married to Princess Cristina, the youngest child of King Juan Carlos and Queen Sofia.

The chief anti-corruption prosecutor for the Balearic Islands, Pedro Horrach, questioned several people Thursday in connection with the probe of the non-profit Instituto Noos.

Horrach has no immediate plans to ask supervising magistrate Jose Castro to subpoena Urdangarin - the Duke of Palma - for questioning as a potential defendant, sources close to the investigation told Efe.