Newspaper leader criticises new industry code of practice.
The legislation, introduced by the Government , means journalists who recommend shares must alert readers or viewers if they have any interest in the stock.
It follows last year's controversy involving The Mirror newspaper when two of the paper's City Slickers journalists were dismissed from their posts after allegations of improper share dealing.
Les Hinton, chairman of the Newspaper and Magazine Publishing Industry's Code of Practice committee and executive chairman of News International, attacked the move in a letter to Economic Secretary to the Treasury Melanie Johnson.
In the letter, Mr Hinton urged the Government to think again on the subject.
He wrote: 'First, the regime you are proposing is completely unworkable. In any newspaper or magazine, a substantial number of people have an involvement in an article - not just the journalist who writes the article, but the commissioning editor, the city or possibly political or home affairs editor, the sub editor, on occasion the picture editor, a copy taker, a lawyer who may clear the article, the deputy editor and the editor.
'Arguably, of course, the publisher is ultimately responsible. Which of these people is to declare an interest? And, if copy is changed after the journalist writes it - in a manner which brings it within the scope to the order - is the originating journalist still responsible?
'In other words, you are proposing a criminal law which is completely unworkable and which will, in effect, be stillborn.
'Second, this order represents the first set of statutory controls that any Government in peacetime has imposed on the press.
'Third, we have consistently made clear that the only effective way to deal with such issues is through self-regulation.'