Allende is mentioned in a book written by the official historian of the British Intelligence MI5 Christopher Andrew. According to SIS and Andrew, the book is based on the handwritten notes of KGB archivist defector Vasili Mitrokhin. Andrew alleges that the KGB said that Allende "was made to understand the necessity of reorganizing Chile's army and intelligence services, and of setting up a relationship between Chile's and the USSR's intelligence services". The Soviet Union observed closely whether this alternative form of socialism could work, and they did not interfere with the Chileans' decisions. Nikolai Leonov affirms that whenever he tried to give advice to Latin American leaders he was usually turned down by them, and he was told that they had their own understanding on how to conduct political business in their countries. Leonov adds that the relationships of KGB agents with Latin American leaders did not involve intelligence, because their intelligence target was the United States. Since many North Americans were living in the region, they were focusing in recruiting agents from the United States. Latin America was also a better region for KGB agents to get in touch with their informants from the CIA or other contacts from the United States than inside that country.