Sony BMG intends introducing new CDs that implement copy protection technology that locks Windows-using iPod owners out.

The new software will be applied across many of the joint firm's forthcoming releases, the company said.

It's the first major label to bring such technologies to the mainstream. Other majors have resisted the move, stating that such technologies are too easy to defeat, and that they would impact against a consumers right to transfer music to portable devices.

Instead, they have been piling pressure on to Apple to "make its technologies compatible with copy-prevention tools".

However, Sony BMG's implementation means Windows users won't be able to transfer their music to an iPod - though they will be able to transfer music to Windows Media-supporting devices.

Thomas Hesse, president for global digital business at Sony BMG told The New York Times: "It's just a proprietary decision by Apple to decide whether to play along or not.

"We think we need to move this forward. Time is ticking, infringement of intellectual property is happening all over, and we've got to put a stop to it I think."