(35) Legal or natural persons conducting direct marketing communications through voice-to-voice calls and through calls by automating calling and communication systems should display present their identity line on which the company can be called. Member States are encouraged to introduce by means of national law a specific code or prefix identifying the fact that the call is a direct marketing call to improve the tools provided for the end-users in order to protect their privacy in more efficient manner. Using a specific code or prefix should not relieve the legal or natural persons sending direct marketing call from the obligation to present their calling line identification.