Complex sentence: The initiative for the meeting came from the new leaders of the HSP, Anto Đapić and Boris Kandare, who invited leaders of the Croatian Pure Party of Rights and the Croatian National Democratic League but the meeting was unsuccessful, and those parties are still acting separately.
Split into simpler sentences: The initiative for the meeting came from the new leaders of the HSP, Anto Đapić and Boris Kandare, who invited leaders of the Croatian Pure Party of Rights and the Croatian National Democratic League. The meeting was unsuccessful, and those parties are still acting separately.