Tension between some of Japan's biggest record labels and Apple remains, with no deal in sight to bring their catalogue to iTunes Japan.

The Daily Yomiuri reports that artists continue to rebel against the labels: Sony Music Entertainment (Japan); BMG Japan; Warner Music Japan and Victor Entertainment. None of these labels have reportedly reached a deal with Apple.

"Singer-songwriter Motoharu Sano, frustrated by the fact that his back catalogue is on Sony and thus not available to iTunes users, is one of several artists who've signed direct deals with iTunes Japan to boost their profile on the local version of Apple's music-download service," the report states.

Sano released a mini-album on August 17 exclusively through Apple's service, which entered iTunes' Japanese chart at number one. He blames corporate bickering for limiting his fan's access to music.

Some label bosses who work for companies which have not yet reached accord with iTunes are encouraging their artists to reach deals with iTunes, the report explains.

It's thought that local market protectionism, competition, and the imminent war on iTunes prices are to blame for the major's seeming lack of mobility on the matter.

"The reality is that iTunes is doing very well," one industry insider told the Japanese reporter, "and artists and their fans want their material available on iTunes."