The Bulgarian Embassy in Havana reports to the Central Committee of the Bulgarian Communist Party and the Bulgarian Ministry of Foreign Affairs on political, economic, and cultural developments in Cuba circa 1963. Cuba is politically united, but is experiencing economic hardship after the “Caribbean Crisis” primarily because of the US embargo. In the report, embassy staff reviews developments between socialist countries and Cuba throughout 1963. Some examples include communist aid to Cuba after Hurricane Flora and Cuba’s stance on Sino-Soviet relations. Bulgaria’s show of solidarity resulted in concrete political, economic, and cultural cooperation. Embassy staff notes the drawbacks and benefits of Bulgaria’s relationship with Cuba.

In his cable to the Bulgarian Foreign Ministry, Ambasador Kiril Shterev reports information about expected US assistance to Greece in 1963. Shterev acquired the information during lunch with the Greek Charge d' Affaires, Counselor Kalougeras. Kalougeras also mentioned Turkey's possible entrance into the European Economic Community and inquired about US-Bulgarian relations.

The Bulgarian diplomatic mission (legation or embassy) to the US reported to the Bulgarian Ministry of Foreign Affairs in Sofia what actions the embassy executed and planned to execute to prevent seizure of documents during the "international situation," or Cuban Missile Crisis. Enclosed in the letter is an explanation of items destroyed and items placed under heightened security. The letter also includes information about security for the embassy staff.