South Korea's gradual lifting of its decades-old ban on the import of Japanese popular culture entered its fourth phase this month, paving the way for the legal circulation of Japanese CDs, game software and all nonanimated films.

But as the deregulation expands to items more readily available for mass consumption, industry players and others are becoming increasingly jittery over the potential negative effects.

The Japanese CD industry, for one, has mixed reactions about the latest move, with many players viewing it as a double-edged sword.