A Spanish judge has ordered the king's sister, Princess Cristina, to be tried along with her husband on charges of tax fraud - making her the first member of the country's royal family to face charges in court since the royalty was restored in 1975.

In issuing the indictment on Monday, Judge Jose Castro went against a prosecutor's December 9 recommendation that Cristina should be fined and only her husband Inaki Urdangarin, a businessman already being prosecuted in the case, should be tried.

The evidence compiled by Castro against Aizoon - a real estate and consulting firm Cristina co-owned with her husband - included suspected abuse of company funds to cover the couple's expenses at their Barcelona home, salsa dancing classes and stays at luxury hotels.

He set bail for her at 2.7 million euros ($3.3m) and 15 million euros for her husband. If convicted, the 49-year-old Cristina could face up to four years in prison.

Damage to image

The case centres on allegations that Urdangarin used his Duke of Palma title to embezzle about 6 million euros ($7.4m) in public contracts through the Noos Institute, a non-profit foundation he had set up with a business partner that channeled money to other businesses, including Aizoon.

Cristina's lawyers have said she is innocent.

The legal troubles of King Felipe VI's sister during a four-year probe seriously damaged the Spanish monarchy's image and were seen as extreme examples of royal excess as the country's unemployment rate rose sharply and the economy nose-dived and nearly imploded in 2012.

Cristina denied knowledge of her husband's activities in February during an unprecedented appearance before Castro to answer his questions.

She and her husband moved to Switzerland in 2013, where she works for the foundation of Spain's La Caixa bank, which finances a variety of programmes to help the needy and promote culture.

Source: Associated Press