Newly declassified archives of the now-defunct Communist regime of Bulgaria revealed that the the regime conspired to set Fener Greek Orthodox Patriarchate in Istanbul on fire, Bulgarian media reported.

Declassified documents of the PGU, the foreign intelligence arm of the Communist regime that run the country until 1991, show a plan to foment crisis between Turkey and Greece, two of the country's neighbors. The patriarchate, an influential entity that controls churches across the globe, was apparently a good target for "Operation Cross" as the plan was called. Documents, which will be included in a book set to be released later this month, show the deputy director of the PGU discussed the plan with other officials in 1970.

If it succeeded, it would strain ties between Turkey and Greece, two NATO allies that already shared a mixed history of hostilities and friendship. Excerpts from the classified document say that the patriarchate is source of political tensions between Greece and Turkey and "an intervention" in the religious entity will "significantly damage Turkish-Greek relations and force the United States to choose one side in the ensuing crisis."

The planned "Operation Cross" would have been set in motion in 1971, with Bulgaria's secret agents arranging the circumstances for a "fire" that would look like the work of Turks. However, the plan was canceled at the last minute.