Apple would drop digital rights management (DRM) technology from the music sold through its iTunes Store if major record companies would allow such a move, Apple chief executive Steve Jobs said in an online post at Apple's website.

Jobs also called on people unhappy with DRM systems - particularly European regulators who want Apple to open its FairPlay DRM to competitors - to push record companies to sell online music without digital-rights restrictions.

"If the big four music companies would licence Apple their music without the requirement that it be protected with a DRM, we would switch to selling only DRM-free music on our iTunes store," Jobs wrote in a post called Thoughts on Music. "Every iPod ever made will play this DRM-free music."

The comments from Jobs come at a time when consumers and European countries are pressuring Apple to loosen the tight ties between music sold at iTunes and Apple's iPod music player. Currently, songs sold through iTunes can only play on iTunes - a restriction common to other digital music retail services.

In his open letter, Jobs said creating a DRM system was a requirement by the major record labels if they were to agree to let Apple sell their music online. Apple's FairPlay lets users play protected songs on up to five computers and an unlimited number of iPods while burning playlists of purchased music up to seven times.

"Obtaining such rights from the music companies was unprecedented at the time, and even today is unmatched by most other digital music services," Jobs wrote.

"However, a key provision of our agreements with the music companies is that if our DRM system is compromised and their music becomes playable on unauthorised devices, we have only a small number of weeks to fix the problem or they can withdraw their entire music catalogue from our iTunes store."

Apple’s boss called DRM-free music "clearly the best alternative for consumers" and one Apple "would embrace in a heartbeat". But that decision hinges on what the four largest music companies - Universal, Sony BMG, Warner and EMI - decide to do, Jobs added. And right now, they're adamant that DRM technology be included with online music.

"Perhaps those unhappy with the current situation should redirect their energies towards persuading the music companies to sell their music DRM-free," said Jobs, noting that two of the four largest music companies have owners located in Europe, where much of the clamour over DRM has taken place. Another, Sony BMG, is half owned by German-based Bertelsmann.

"Convincing them to license their music to Apple and others DRM-free will create a truly interoperable music marketplace," Jobs said. "Apple will embrace this wholeheartedly."

A path that Apple won't embrace, however, is licensing FairPlay to competitors. That would require Apple to disclose proprietary technology to people outside the company, Jobs said, inevitably leading to leaks.

"The internet has made such leaks far more damaging, since a single leak can be spread worldwide in less than a minute," Jobs wrote. "Such leaks can rapidly result in software programs available as free downloads on the internet which will disable the DRM protection so that formerly protected songs can be played on unauthorised players."

Jobs also spends his open letter noting that it's difficult for a DRM system to work since music companies sell 10 times the amount of songs sold online via CDs with no DRM. Users can rip those CDs and upload those music files to the internet for others to download.

"So if the music companies are selling over 90 percent of their music DRM-free, what benefits do they get from selling the remaining small percentage of their music encumbered with a DRM system? There appear to be none," Jobs said.

Jobs also disputed the notion that DRM systems tie users to a particular music player or store. According to Jobs, Apple has sold 90 million iPods and 2 billion songs - or 22 songs purchased for every iPod ever sold. By Jobs' math, that accounts for less than 3 percent of the music stored on an iPod capable of holding 1,000 songs that's filled to capacity.

"It's hard to believe that just 3 percent of the music on the average iPod is enough to lock users into buying only iPods in the future," Jobs said.