Leaders of the battle against child-sex tours have recently called on major Japanese travel groups to join a growing international campaign against the widespread practice.

The call comes prior to the second World Congress against the Commercial Sexual Exploitation of Children, to be hosted by the Japanese government in Yokohama in December.

The first World Congress, patronized by Sweden's Queen Silvia in 1996, included delegates from over 120 countries and brought worldwide attention to the issues of child pornography, trafficking and prostitution.