Dumfries House said that it accepted the artworks in good faith and played no role in verifying their authenticity.
The Prince of Wales, an amateur painter himself, was also not involved in the selection of the artworks, they said.
“Dumfries House accepts artwork on loan from time to time from individuals and organisations such as the Scottish National Gallery,” a Prince’s Foundation spokesman told PEOPLE in a statement.
“It is extremely regrettable that the authenticity of these particular few paintings, which are no longer on display, now appears to be in doubt.”
According to the Mail, the three paintings in question form part a wider collection of 17 artworks loaned to Dumfries House by former bullion dealer James Stunt, who separated from Formula 1 heiress Petra Ecclestone in a $7 billion divorce in October 2017.
The Monet is reported to be entitled Lily Pads 1882 and was authenticated by the prestigious Wildenstein Institute in Paris.
The Picasso is called Liberated Bathers and shows two figures on a beach. The Dali is a surreal play on a traditional crucifixion scene called Dying Christ.
“None of these pictures have come back, they are all there,” Stunt told the Mail when questioned about the alleged forgeries.
“No Monet has come back to me because it is not real.”
He added, “None of my stuff is fake.”
In contrast, forger Tony Tetro told the outlet: “There is no question about it: James knew they were mine.”
Tetro has explained some of his techniques to BBC TV show Fake or Fortune in the past.
"I'm happy to do it. It's my job. It's like getting up in the morning and brushing my teeth and having breakfast, I get up and paint and age a masterpiece," he said on the show.