The Greek version of Big Brother has been told it wants to know too much - by Greece's Data Protection Authority.

The independent agency said it was "unconstitutional, illegal, and unethical" for producers of the reality TV programme to create a database of personal details provided by thousands of potential contestants.

The Antenna television station is planning to show the programme in the autumn.

Twelve contestants will be locked in a house for 112 days with their every move caught on camera.

The application form asks 80 questions, and candidates have to give tax information and details about friends and relatives.

"For there to be a legal archive, its purpose must be legal," the authority said.

In Greek law, it is illegal to retain data on people without permission from the government or the authority.

Dignity

The Data Protection Authority said it was a matter of dignity.

"For the small chance of a profit and attaining fame, a person alienates his personal life and becomes a viewer's prey," the authority said in its decision, quoted by the Associated Press.

"A person is humiliated many times without him even realizing it."

Following the decision, the production company ENA must stop collecting information from the applications.

The show has already met opposition in Greece before it has even started.

Journalists, regulators and students have expressed concerns that it will drag the standard of television to a new low.

Greece's National Council for Radio and Television is worried that the show could violate obscenity rules.

Guidelines were tightened after another channel aired footage of a Greek pop singer having sex last year.

Big Brother's voyeuristic style has already polarised audiences and sparked debate in France, Portugal, Italy and Australia.

But it has been a ratings-winner in almost all of the 15 countries where it has been shown.