Greek PM addresses Concordia Europe Summit in Athens
summit
Tsipras hopes to meet with European leaders on sidelines to promote Greece's case on debt relief
Summit at Bari on may 11 and 13
EU will remain united or fail completely, says Tusk
Greek PM post-EU summit press conference
Mr. Tsipras also commented on refugee crisis
Greek PM to meet with EC President Juncker and French President Francois Hollande
Agenda of talks to include US election results, among other issues
Numerous NGOs and social groups to participate