David Elstein, former Channel 5 chief executive, has said newspaper and magazine publishers need to band together so that they are not "held to ransom" by digital companies such as Apple.

Elstein, speaking at the Oxford Media Convention on Wednesday, was asked for his view of the power of Apple as a gatekeeper for digital publishers offering digital content online.

Apple, which runs an e-store called Apple Newsstand, takes as much as 30% of revenues from publishers that launch apps and offer content on its platform and devices.

"It is very important for publishers of news to get together in groups so they are not held to ransom by intermediaries," he said. "Those who get a temporary economic advantage [like Apple] can consolidate quite extensively before the rest of the world catches up with them."

Robert Shrimsley, managing editor of FT.com, pointed out that the Financial Times decided that it needed to launch a digital news app using HTML5 technology after deciding that Apple's terms were onerous. He said that a number of publishers have followed such a strategy to look to decrease reliance on Apple, such as the New York Times.

Shrimsley also highlighted the importance of publishers controlling as much of the revenue as possible from mobile devices.

"We think that 50% of our digital readers will be accessing content on mobile devices in the next two or three years, as opposed to on laptops," he said.

He added that digital subscriber numbers passed the FT's global newspaper subscription numbers last year for the first time.

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