Just one week after the funeral of Benedict XVI, his closest aide released a much-trailed memoir Thursday, revealing details of tensions between the late pope emeritus and his more liberal successor Pope Francis.

Georg Gaenswein's book reveals private conversations with both popes in charting the German ex-pontiff's rise to power and the decade spent in retirement following his shock resignation in 2013.

The Vatican has not officially responded but Pope Francis called Gaenswein in to a private meeting on Monday, following days of pre-publication interviews in which the 66-year-old German aired years of grievances.

In one, he claimed it had "pained Benedict's heart" when Francis effectively reversed his predecessor's decision to relax restrictions on the use of the traditional Latin mass.

Up until his death on December 31 at the age of 95, Benedict had remained a figurehead for the conservative wing of the Catholic Church, which views Pope Francis as too liberal.

- Shocked and speechless -

As his secretary since 2003, Gaenswein was a constant presence at Benedict's side, and during his final years living in a monastery in the Vatican grounds, his gatekeeper.

After Benedict's death, Gaenswein led the mourners, greeting visitors to his mentor's lying-in-state and kissing the coffin in front of tens of thousands at St Peter's Square during the funeral led by Pope Francis.

In "Nothing But the Truth: My Life Beside Pope Benedict XVI", Gaenswein describes Benedict's perplexity at some of Francis's decisions, and the latter's apparent attempts to keep his predecessor in check.

After becoming in 2013 the first pope in six centuries to resign, Benedict promised to live "hidden from the world", but broke that pledge to speak out on several explosive issues.

The last straw appears to have been a book Benedict co-authored on priestly celibacy in 2020 -- a PR disaster that Gaenswein said Francis appeared to blame in part on him.

Gaenswein was effectively fired as head of the papal household with immediate effect.

"Stay home from now on. Accompany Benedict, who needs you, and act as a shield," he said Francis told him.

Gaenswein, who had been propelled into the limelight on Benedict's election, says he was left "shocked and speechless" by his demotion.

On hearing the news, Benedict half-jokingly said "it seems Pope Francis doesn't trust me anymore, and is making you my guardian".

The ex-pontiff intervened and tried to get Francis to change his mind, but to no avail, Gaenswein wrote.

- 'Gorgeous George' -

Like Benedict, Gaenswein was born in Bavaria. He describes his young self as "a bit transgressive", sporting unruly locks and listening to Pink Floyd.

The son of a blacksmith, he was ordained in 1984 and rose through the ranks to become secretary to the then-Cardinal Joseph Ratzinger.

When Ratzinger was elected to the papacy in 2005, the international media was instantly smitten by his dashing blond-haired assistant.

He was nicknamed "Bel Giorgio" ("Gorgeous George") and gossip magazines gleefully began splashing paparazzi-style photographs of him in his tennis whites.

His close relationship with Benedict sparked jealousy, he said in the memoir.

But the new pope, Francis, appeared not to want him nearby, Gaenswein said, citing the pontiff's refusal to allow him to live in the palace apartment that Benedict had used.

The memoir is not expected to improve relations between the pair, and it was not clear what job Gaenswein will be given now.

Some Vatican commentators have speculated he could be appointed as a Vatican ambassador, or as director of an important shrine.

© Agence France-Presse

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