However, when contacted by BuzzFeed News, Gordon distanced himself from the story and said his quote had nothing to do with Short money, the term for the public funding opposition parties receive.

"My reasoning that refusal of a place [on the Privy Council] could (the word I allowed to be cited) raise constitutional issues was not related to Short money," he wrote in an email (emphasis his). "It was based on the constitutional relationship between the monarchy and main political party as the official opposition."

Instead, the issues Gordon said could be raised by a refusal to join the council related to the constitutional relationship between the opposition and the crown.

"However, I have little doubt that in the longer term and in practice that relationship could be changed," he continued, "which was why in the phrase I allowed to be quoted I suggested that the issues if they arose would be 'short-term'."

In practice, such issues will not arise as Corbyn yesterday accepted a place on the council. He is believed to have done so to more easily receive briefings on security issues.

No other experts are quoted in The Sun's story to support its front-page claim.