"I (Mehmet Ali Agca) asked the Turkish government to release me for one day so that I can discuss theological issues with (Pope) Ratzinger," Agca said in comments passed on by his lawyer Mustafa Demirbag at a news conference.
"I want to discuss with him religious and mystic issues," Demirbag quoted Agca as saying.
Agca is serving a sentence for the killing of a newspaper editor in the 1970s and for robbery and is scheduled to be released from prison in 2010.
The former right-wing gangster served 19 years in an Italian prison for his attempted assassination of John Paul, before being pardoned at the late pope's behest in 2000 and extradited to Turkey.
The lead-up to Benedict's first visit to a Muslim country has been peppered with controversy. Turkish government leaders have been accused of reluctance to meet him, street protests have erupted against the visit and a gun was fired outside the Italian consulate in Istanbul.
Agca's motives for shooting Pope John Paul in Rome's St. Peter's Square remain a mystery. Some believe he was a hitman for Soviet-era East European security services alarmed by the Polish-born pontiff's fierce opposition to communism.