An Argentinian rape victim has claimed that she got a surprise call from Pope Francis, who has made a habit of ringing up random worshippers to directly bring words of comfort or encouragement.

Alejandra Pereyra, 44, said she was petrified when told that her caller was Pope Francis.

"When I heard the Pope's voice I felt like being touched by God," Pereyra, from the city of Cordoba, told local Canale 10 television.

The pontiff reportedly rang her after receiving a letter from Pereyra telling of the pressure she had been put under when she accused a police officer of raping her.

Pereyra said she chatted with the Pope for about 30 minutes.

"We talked about faith and hope," the woman said. "The Pope listened carefully to my story.

"He told me he receives thousands of letters a day but mine really touched his heart."

The Argentinian pontiff, who has set a new a down-to-earth approach in the Vatican, also reportedly invited Pereyra to the Holy See.

"Now I know I'm not alone and that I'll be able to stand up again." Pereyra said. "He told me to have faith in justice."

Pereyra is not the first surprised recipient to pick up the phone and hear: "Hello there, it's Pope Francis."

Earlier in August, he called - twice - the family of an Italian businessman who had been shot dead during a robbery in Italy.

Francis first called Michele Ferri, brother to 51-year-old Andrea who was murdered in June. A couple of weeks later the Pope rang again to speak to the 77-year-old mother, Rosalba.

"When he told me he was going to call back to speak to my mother I thought he would have done so in one year time or so. Instead, he kept his word," Ferri said.

Not only crime victims are known to have received calls from the Vatican. Recently, it was the turn of Stefano Cabizza, a 19-year-old engineering student from Padua, who had sent Francis a letter three days earlier.

Cabizza was not home when Francis called so the pontiff left a message with the student's sister who reportedly thought it was her brother's football coach. The Pope called back a few hours later.

Francis' buzz frenzy has also prompted Italian columnist Beppe Severgnini to write a short hand guide for properly receiving a pontiff's call.

Severgnini's suggestions published in Italian Il Corriere della Sera newspaper include: always ask how Benedict XVI is doing and avoid touchy subjects like Vatican scandals.

The Vatican was unavailable for comment.