A renowned American art forger has controversially claimed that numerous paintings displayed at the headquarters of Prince Charles’ Foundation are fakes.

Artworks by Claude Monet, Pablo Picasso and Salvador Dalí, valued at £100 million, have since been removed from Dumfries House in Scotland. “It is extremely regrettable that the authenticity of these paintings, which are no longer on display, appears to be in doubt,” clarified a spokesman for the royal foundation.

The paintings formed part of a larger 10-year loan to the foundation from James Stunt, a bankrupt former bullion dealer and art collector.

Known as “the single largest forger of art works in America”, the infamous Tony Tetro revealed on Monday that he had painted at least three of the works on loan to the 18th-century estate. Although Tetro pleaded no contest to forging paintings in 1993, he now makes a legal living selling fakes for the private use of his clients.

None of the paintings currently under scrutiny “could possibly be construed as real,” asserted Tetro. He alleges that Stunt commissioned him to create the works between 2015 and 2017 for private use only.

According to Tetro, Stunt had specifically requested that the paintings look as realistic as possible: “I aged all his pictures artificially—that costs extra… James’s ambition was to hang them on his wall and impress his friends.”

By splashing the canvases with coffee and bleach, Tetro managed to create the illusion of age. Yet this method would not fool any art expert, as the forger explained “the pigments, materials, canvas, stretcher bars and other details could be easily detected [as modern] by even the slightest inspection, and this was done purposely so as to avoid any confusion.”

Tetro has only spoken out now because Stunt has supposedly attempted to sell the forgeries as originals on the secondary market to help pay his debts.

“None of my stuff is fake” insisted Stunt, who categorically denied the claims made against him of art fraud. As the ongoing investigation by Dumfries House  has become more intense, Stunt has since issued “huge apologies” to Prince Charles.

In an Instagram video on Saturday Stunt maintained that the works were genuine, but also proposed the following scenario: “let’s say they were fake. What is the crime of lending them to a stately home, [to] the Prince of Wales and putting them on display for the public to enjoy?”

The Prince of Wales is not directly involved in the counterfeit art debacle, although Tetro felt the need to apologise to the royal as well. “I would like to say that I’m very sorry if Prince Charles was embarrassed by this,” said Tetro, “it’s the last thing I thought could ever happen.”