In an interview Cinema Cafe, Naruto manga artist Masashi Kishimoto revealed his thoughts on his relationship with One Piece (be sure to check out this post for further context before reading further).

[After seeing One Piece‘s cover page, I] immediately turned to LINE (a popular messaging service used in Japan) and went on to thank Eiichirō Oda myself, not only for the cover, but also because of his comment in Weekly Shonen Jump where he called me his “colleague, friend and rival” which is how I thought of One Piece — and Oda-san — during Naruto‘s serialization, so that made me really happy.

Kishimoto also commented on whether he was “aware” of One Piece: