Germany's Bild Zeitung newspaper said the Vatican's Financial Information Authority was investigating a USD 21-million deal by the Vatican bank with the Italian company Lux Vide owned by Ettore Bernabei.
The 79-year-old Tarcisio Bertone, the Vatican's former secretary of state and then head of the bank's oversight committee of cardinals told the Adnkronos news agency that the deal with Lux Vide had been regularly approved.
The ANSA news agency also quoted Bertone as saying that there was "no problem linked to this operation".
"I don't understand these attacks," said Bertone, who was replaced last year by Pope Francis with Pietro Parolin as secretary of state -- a role equivalent to prime minister.
"I am in harmony with the pope... He likes me," he said.