Shafaqna (International Shia News Agency) – The Grand Ayatollah Sistani answered some questions regarding male and female relations. According to Shafaqna the questions and answers are as follows:
Question 1: I want to ask about talking to ones fiancee on telephone, is it permissible or not?
Answer: If there is no such a fear that you might fall into a sin, there would be no problem.
Question 2: Is it permissible to chat with girls on the internet?
Answer: If there is a fear that a girl or a boy may be drawn towards sin, it is not permissible. Normally chatting ends up in a sin for both sides.
Question 3: Is it permissible for a boy of fifteen years to have a girl friend?
Answer: Friendship with a non-mahram is not allowed.
Source: Ayatollah Sistani