He told the Lords yesterday that he is opposed to changing legislation to allow large newspaper groups to own Five or any other terrestrial broadcaster.
He said that diversity would be killed should one of these groups win control of Five. "What is absolutely certain is that plurality and diversity are not a natural by-product of unregulated market forces. It is for this reason I will be opposing in every respect the provision that would allow Five or any terrestrial channel to be wholly or partially owned by any large newspaper group," he said.
His main concern is that BSkyB owner Rupert Murdoch would cross promote any terrestrial service he owned over his "dominant satellite position" and his newspaper holdings, "entirely without precedent".
He said this could destroy public service broadcasting if legislation allowing it was not removed. He said: "The law of unintended consequences will bear down and never again will any secretary of state be able to celebrate Britain as the home of the 'best free broadcast media in the world'."
Lord Puttnam is expected to be backed up by around 60 peers including broadcaster Lord Bragg, who are expected to rebel against the bill.
The Liberal Democrats are already opposed to the rule, while the Tories are in favour of liberalisation of the current clause. However, Lord Puttnam says that the government can only rely on 30% of their own vote, as peers worry that Murdoch would have unchecked power if he took ownership of Five and that there needs to be some concessions in place.
Lord Puttnam chaired the scrutiny committee into the government's communications bill, and recommended that plans to relax the ban on newspaper proprietors owning terrestrial television stations be dropped.
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