Washington - "If things get sticky Mr President you can always tell him one of your, uh, altar boy jokes," the head of the Secret Service chuckled today, "the one about anointing with Ecuadorian oils bound to be to his taste."
The pre-visit prepping this weekend sees Barack Obama poring over Roamin Catlick ecclesiastical etiquette from an official diplomatic primer researched by the CIA.
Mostly inter-ecumenical chit chat about 'The Holy Hand Grenade of Antioch' and other iconic passages sourced from the Holy Book of Armaments.
The essential reading comes ahead of Thursday's meeting deep beneath the Roman Catacombs in the private Pontifical bat cave where the two leaders are scheduled to talk man to man.
President Obama will then hand over the Argentinian pope's secret CIA file and shake hands on a hush-hush new deal to obliterate the pesky Mexican drugs problem that's wreaked havoc all over joint US/papal turf.
An exchange of gifts commemorating the summit will then take place.
Capitol Hill sources remain a bit vague about what Obama may give Pope Francis in exchange for the rumored box of 50 Finest Havana Cigars but the smart money's on half a kilo of Denver Devilsclaw Sinsemilla Weed.
The Patriarch of Constantinople is a crystal meth fiend.