Prince Charles is meeting ministers so he can pursue his own political interests, according to anti-monarchy group Republic.
The Prince of Wales has held private meetings with Cabinet ministers 36 times since the last general election.
Republic chief executive, Graham Smith, said the Prince of Wales was clearly choosing ministers to meet who are relevant to his own personal interests.
Mr Smith said the public needed to have a clear understanding over what the Prince's interests are, and whether those interests are impacting on public policy.
More top news
Jonny Evans and Papiss Cissé are facing likely bans from the FA after appearing to spit at each other during a Premier League game
Tony Iommi has appealed to metal-loving Indonesian President Joko Widodo to spare the lives of two Australians on death row.
Madame Tussauds has released the first images of the early work in progress of Luke Skywalker, Han Solo and Princess Leia's wax figures