A Freedom of Information request which was fought by the Cabinet Office has disclosed that a minimum of 39 Bills have been subject to the little known Royal prerogative that permits the Queen and Prince Charles to consent to legislation before it is passed.

The disclosure was ordered by the Information Commissioner.

“Ministers and civil servants are obliged to consult the Queen and Prince Charles in greater detail and over more areas of legislation than was previously understood,” the Guardian newspaper claimed.

"This is opening the eyes of those who believe the Queen only has a ceremonial role," Andrew George, Liberal Democrat MP said.

"It shows the royals are playing an active role in the democratic process and we need greater transparency in parliament so we can be fully appraised of whether these powers of influence and veto are really appropriate. At any stage this issue could come up and surprise us and we could find parliament is less powerful than we thought it was."

John Kirkhope is a notary public who submitted the Freedom of Information request.

"There has been an implication that these prerogative powers are quaint and sweet but actually there is real influence and real power, albeit unaccountable," he said.

In similarly worded statements, representatives for both the Queen and Prince Charles said that neither had refused to consent to any bill affecting their interests unless advised to do so by ministers.