Princess Mary and Prince Frederik of Denmark Step Out Together as Socialite Denies Affair with Future King

Crown Princess Mary and Crown Prince Frederik put on a united front on the same day that a socialite denied romance rumors with the future king.

On Tuesday night, Princess Mary, 51, and Prince Frederik, 55, stepped out at the Glyptoteket Museum in Copenhagen with Frederik’s mother Queen Margrethe and his aunt Princess Benedikte during the Spanish state visit to Denmark. The Danish royals are hosting King Felipe and Queen Letizia for a three-day stay, and the group capped day two by viewing the “Joaquín Sorolla – Light in Motion” exhibit followed by a dinner.

Crown Princess Mary and Crown Prince Frederik smiled as they arrived, and the future monarch put his hand on his wife’s back as they walked into the museum.

And in a subtle message, Crown Princess Mary accessorized with a necklace featuring the initial "F." She wore the piece of jewelry nodding to her husband before on several occasions, including at King Charles' coronation in May.

The outing came amid gossip about the heir to the Danish throne. According to Hola!, rumors of a romance surfaced after Spanish outlets published photos of Crown Prince Frederik with philanthropist, model and TV personality Geneveva Casanova during his private trip to Madrid. The outlet reported that the two toured a Picasso exhibit at the Thyssen-Bornemisza National Museum, walked through a park and had dinner together in the heart of the city. The outing reportedly came to be because a mutual friend who was originally set to accompany Frederik around Madrid got sick, and asked Casanova, who is an expert in Picasso art, to go in his stead.

Denying the buzz, Casanova told Hola!, "I flatly deny the statements that suggest a romantic relationship between Prince Frederick and me. Any statement of this type is not only completely untrue but also distorts the facts in a malicious manner. This is already in the hands of my lawyers, who will take care of the pertinent steps to protect my right to honor, truth and privacy."

Danish news site Dagens.com states that Prince Frederik’s trip to Spain fell while his wife was in New York for United Nations Day. While Princess Mary’s N.Y.C. stay from Oct. 23 to 24 was announced by the Danish Royal House, Prince Frederik’s trip to Spain was not.

Dagens.com reported that Casanova, who was born in Mexico and is based in Spain, previously had a royal romance of her own. The socialite was previously married to Cayetano Martínez, an Olympic equestrian and the current Duke of Arjona.

Crown Prince Frederik and Crown Princess Mary celebrated 19 years of marriage in May and first connected through an unexpected meet-cute.

They met at a bar in Sydney, Australia in 2000, where Prince Frederik was visiting for the Summer Olympics. Mary Donaldson, an Australian advertising executive, found herself chatting to “Fred” and instantly hit it off.

"Something clicked," Princess Mary later explained in a 2005 interview. "It wasn't the fireworks in the sky or anything like that, but there was a sense of excitement."

Shortly after, Mary found out that she was talking to the Crown Prince of Denmark, heir to the 1,000-year-old Danish throne.

"The first time we met, we shook hands," she recapped of their introduction. "I didn't know he was the prince of Denmark. Half an hour later, someone came up to me and said, 'Do you know who these people are?' "

The couple dated long-distance before getting engaged and married at Copenhagen Cathedral in 2004, and they went on to welcome four children: Prince Christian, 18, Princess Isabella, 16, and 12-year-old twins Prince Vincent and Princess Josephine.

As full-time working royals — and the future king and queen of Denmark — Frederik and Mary support Queen Margrethe and the crown through royal engagements and many patronages.

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As part of their royal responsibilities, the Crown Prince couple greeted King Felipe, 55, and Queen Letizia, 51, at Copenhagen Airport as their state visit began on Monday. The couple has played a key role in hosting since, from the glam state banquet at Christiansborg Palace to a wreath-laying at The Citadel and stops at Copenhagen City Hall, the University of Copenhagen and the Danish Architecture Center.

King Felipe and Queen Letizia’s trip to Denmark wrapped on Wednesday, and they participated in tradition by signing a guestbook — and a window pane! — with Queen Margrethe at Fredensborg Palace. 

“It is a more than 160-year-old tradition in the Danish royal house that the regent's guests, if they are of princely rank or heads of state, sign a window pane when saying goodbye after a state visit 🖋️,” the court wrote on Instagram, adding that the pane will now hang in the North Zealand castle.

King Felipe and Queen Letizia’s state visit to Spain was the first in 43 years, as his parents King Juan Carlos and Queen Sofia last visited in 1980.