Apple has signed up a second film studio to sell content through its iTunes download store. 

Paramount has agreed to sell 100 of its library titles as downloads, although new films will not be included in the deal. 

Disney was the first studio to sell videos through the iTunes store, racking up $1m (£531,000) in sales in the first week with 125,000 downloads.

Apple chief executive Steve Jobs claimed in his Macworld keynote address that more than 1.3 million movie downloads have been sold through iTunes since September 2006.

Sales of television downloads have attracted more backers, and Disney's output has been followed by programmes from Showtime, NBC Universal and MTV. 

Film studios are unhappy at the $12.99 (£6.70) price tag for new films from iTunes, because studios make smaller profits at that price. They also risk creating a rift with traditional DVD vendors which sell the films at a higher cost.

Paramount head Brad Grey confirmed that it was the company's efforts to treat bricks-and-mortar retailers in an equitable way that had restricted it to selling library films on iTunes.

Paramount has agreed to sell its older movies on iTunes for $9.99 and expects the initial choice of 100 movies to double by the end of the year.