The upcoming state visit to Cuba by Party General Secretary and State President To Lam is expected to usher in a new phase in the cooperation and special friendship between the two countries, with more substantive and sustainable results, a Vietnamese diplomat has said.In an interview granted to the Vietnam News Agency (VNA), Vietnamese Ambassador to Cuba Le Quang Long said the visit holds significance, adding it is Lam's second overseas trip and his first visit to Cuba in both his roles as Party General Secretary and President of Vietnam.Source: Vietnam News Agency