The government has attempted to reverse key changes to the Communications Bill.

Culture secretary Tessa Jowell urged MPs to reject a series Lords amendments concerning the creation of a regulator for the media industries.

Jowell warned that the changes made by peers to the government's legislation would leave Ofcom vulnerable to legal challenges by big foreign firms hoping to take over British TV stations.

"I am advised that keeping the bill as it stands leaves Ofcom vulnerable to legal challenge. I can assure the House that the government also clearly understands the difference between the interests of the consumer and the interests of providers," she told MPs.

"Our amendments remove any potential dangers contained in differing interpretations of the previous amendments while maintaining the concept that Ofcom shall have a primary duty to both citizens and consumers."

Jowell told MPs that both Lord Currie, who is set to become the new regulator, and Lord Puttnam, who led the committee which probed the bill, backed the government's changes.

For the Conservatives, shadow culture secretary John Whittingdale signalled that the party was prepared to reach a consensus with the government.

He warned that at the heart of the issue was the problem of a watchdog with a dual role of protecting both citizens and consumers.

It would prove difficult to be both the economic and content regulator, Whittingdale predicted.

"We have always been sympathetic to the idea of bringing together the five different regulators into a single body," he warned.

"But nevertheless it will often have to undertake two very different functions and there may occasionally be times when they come into conflict."