A royal chauffeur allowed undercover reporters into Buckingham Palace in exchange for money, it has been reported.
The News of the World says Brian Sirjusingh was paid $1,600 by its reporters in exchange for access to the building.
Once inside, he showed them several vehicles used by members of the Royal Family.
One was even allowed to sit in a Bentley used to transport the Queen on state occasions.
Strict security measures are meant to be in force at the Palace.
Even members of the Royal Family including Prince Charles must show photo ID each time they enter a royal residence.
Surjusingh apparently boasted of how he underwent a year's special training to prepare him for his job.
He thought the reporters, who he had never met before, were wealthy Middle Eastern businessmen.
According to the News of the World, he spoke indiscreetly about the Queen's movements, giving away confidential security details.
A spokeswoman for the palace said: "Any security matter is taken very seriously and we will look into these allegations."