Downloads of Walt Disney films on the iTunes platform have risen sharply to more than 1.3m after only three months on sale, putting pressure on other Hollywood studios to join Apple’s digital service.

Disney began selling its new movies on iTunes in October. But other studios have resisted its lead, partly because of fears that they will upset retailers such as Wal-Mart and Target, which are responsible for most DVD sales in the US.

Target has expressed concerns about the effect of downloading on DVD sales and pricing. But in an exclusive video interview on FT.com, Bob Iger, Disney’s chief executive, said digital distribution was “creating more consumption of media”. He added: “The message that we deliver to our traditional [retail] partners is that the pie is getting bigger.”

Video

Bob Iger talks to US Managing Editor Chrystia Freeland in an exclusive video interview

He dismissed fears that digital downloads would cannibalise DVD sales, pointing to record sales of Cars, a Disney animated movie, and of Pirates of the Caribbean: Dead Man’s Chest, which is on course to be the biggest selling DVD ever.

Mr Iger said retailers’ concerns were to be expected but Disney had to sell content on digital channels. “If we don’t put our content on these platforms, which the consumer has obviously embraced, other entities will create content and fill that void.”

The launch of Pirates of the Caribbean and Cars on iTunes helped push Disney download sales through the 1m barrier, with the total number of Disney downloads sold on iTunes doubling over the Christmas period.

Disney also put its TV programming on iTunes a year ago and has sold more than 20m downloads.

The company’s buoyant DVD sales come as the media industry braces itself for a DVD slowdown. After several years of growth, the market is maturing.

Pali Capital, a research firm, expects 2007 to be the first year that spending on DVDs in the US declines.