Pope Francis prepared to go face to face with his predecessor Benedict XVI on Saturday in a historic meeting between two men with very different styles but important core similarities.

The Argentine pope was expected to take a helicopter from the Vatican landing at around 1115 GMT at the papal residence of Castel Gandolfo near Rome where the "pope emeritus" has been living since his resignation last month.

The meeting between a pope and a former pope is believed to be a first for the Catholic Church as Latin America's first pontiff embarks on a papacy fraught with challenges that sometimes overshadowed Benedict's reign.

Benedict has been staying at the lakeside estate since he became the first pope to resign in more than 700 years and the Vatican said he followed television news coverage of Francis's momentous conclave election last week.

The Vatican has said the meeting is private and the content of talks between the 76-year-old Argentine and the 85-year-old German will remain secret.

The two are expected to both wear their white papal vestments. The two are expected to have lunch for talks lasting until around 1300 GMT.

Francis has paid homage to Benedict and analysts say he is likely to rely heavily on the towering theological legacy left behind by the former pope. Benedict, before he stepped down, pledged allegiance to whoever his successor might be.

For the two leaders of the world's 1.2 billion Catholics there could be many weighty issues on the agenda including rising secularism in Western countries, the reform of Vatican bureaucracy and the scandal of clerical child abuse.

Italian media reported ahead of the meet that Benedict, who stunned the world on February 11 by announcing that he was too frail in body and mind to carry on, has prepared a 300-page handwritten memorandum for his successor.

The two could also discuss "Vatileaks" -- a scandal that broke last year over the leaks of hundreds of confidential papal documents that revealed allegations of intrigue and corruption inside the secretive Vatican.

Three cardinals conducted an investigation into the leaks which they have written up into a report on the inner workings of the Vatican that Benedict said should only be for the eyes of his successor.

Benedict has said he will live "hidden from the world" as a "simple pilgrim" on life's last journey and is expected next month to move back and live in a former nunnery on Vatican grounds in quiet contemplation and academic research.

Benedict is living temporarily in Castel Gandolfo with his secretary Georg Gaenswein -- who confusingly is also the head of his successor's papal household -- and with the four housekeepers who looked after him when he was still pope.

Since his election last Wednesday, Jorge Bergoglio has called his predecessor up twice. The last time was on the day of his inauguration on Tuesday when he congratulated Joseph Ratzinger on his name day of St Joseph.

The two have known each other for a long time. At the 2005 conclave, Bergoglio was the main rival to Ratzinger and represented a more socially progressive current among the cardinals. But he pulled out of the race.

While Ratzinger was reserved in public, Bergoglio is more spontaneous and people-friendly and has shunned some of the trappings of papal office.

Ratzinger was more a follower of tradition and never liked innovation.

But the two are very alike on doctrine and several of Francis's remarks in the first days of his papacy have been borrowed from his predecessor.

Both are opposed to gay marriage, abortion and euthanasia -- which Catholic believers considers a form of interference with God's "creation".

Francis's popularity is being seen with bitterness in some Vatican quarters where the memory of Benedict still shines strongly, unlike in the minds of many ordinary Catholics who have said they prefer the new pope's more direct style.

When he takes up residence in the Vatican, Benedict will be just a stone's throw from Francis -- an unexpected and delicate situation, for the Church.

"This papacy will be rooted in Benedict's teachings," Samuel Greggo from the US-based Acton Institute religious think tank.

"For the past 25 years, he has been the main intellectual force in the Church," said Samuel Gregg from the US-based Aston Institute religious think tank.