Pope Francis has used his annual Christmas address to some of Catholic Church’s most senior clergy members to highlight the power-hungry, “diseased” culture of the Vatican.

In his Monday speech, Pope Francis accused the priests, bishops and cardinals of suffering from “existential schizophrenia” and “spiritual Alzheimer’s”, adding that many are guilty of “rivalry and vainglory”.

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“The Curia needs to change, to improve,” Francis said of the central administration of the Roman Catholic Church.

“A Curia that does not criticise itself, that does not bring itself up to date, that does not try to improve, is a sick body.”

The Pope, who has made plain his desire to avoid the perks of his office and bring the church closer to its people, went on to compare the Curia to an “orchestra that plays out of tune”.

He urged his brothers to steer clear of the gossip that plagues the Curia and contributes to the “pathology of power”.

“Brothers, let’s guard ourselves from the terrorism of gossip,” Francis urged the meeting’s attendees, adding many acted as if they were “immortal, immune or even indispensable”.

“This is a serious disease that begins simply when people chatter, and it takes over the person, turning the person as a Satan, and in so many cases people are speaking ill about their own colleagues and brothers and sisters. These people haven’t got the courage to speak directly, and they speak about others behind their backs.”

Pope Francis concluded the annual address, which typically involves an exchange of pleasantries, by calling on the administration to rid itself of its “diseases”.

“Dear brothers, such diseases and such temptations are a naturally a danger for each Christian and for each Curia,” he said.

“For each community, for any ecclesiastical movement. They can damage both individually and the community. We have to say that only the Holy Spirit and the soul of Christ, only he can protect us from the disease.”