Iran is willing to build a refinery in Bulgaria's Varna on the Black Sea, according to Tehran's Ambassador to Sofia Gholam Reza Baqeri Moqaddam, Sofia News Agency (Novinite.com) has reported. "As far as Iran is concerned, there is no problem for realizing this project - whether from the point of view of science, technology, capital, or management", Moqaddam has added.