German mobile operator, T-Mobile International, is to lose its chief technology officer, Joachim Horn, at the end of March.

T-Mo, which is owned by German incumbent Deutsche Telekom, said Horn is leaving to pursue a “new professional opportunity” outside Germany.

During his five year tenure at T-Mobile, Horn is largely credited with the large scale network modernisation in the core, radio and service platforms. He also laid the foundation for a successful mobile broadband business at T-Mobile by introducing both HSPA and Edge in the European networks.

The company said a successor will be announced in the near future.