Pope Francis has laid into the Vatican bureaucracy in a pre-Christmas address to cardinals, accusing it of being self-satisfied and having "spiritual Alzheimer's" while succumbing to "the terrorism of gossip."

At the traditional year-end meeting Francis laid his criticism at the administrative group known as the Curia, which plays a pivotal role in running the Roman Catholic Church as suffering from 15 "ailments."

"The first is "the sickness of considering oneself 'immortal', 'immune' or 'indispensable', neglecting the necessary and habitual controls.

"A Curia that is not self-critical, that does not stay up-to-date, that does not seek to better itself, is an ailing body," Francis said in his speech released by the Vatican news service.

Francis who has been seen as a pontiff seeking to modernize the Catholic Church, portrayed the Curia as a group consumed by gossip and egotism.

"It is the sickness of the rich fool who thinks he will live for all eternity, and of those who transform themselves into masters and believe themselves superior to others, rather than at their service."

The first Latin American pontiff said he wanted to see changes for the better, citing "freshness, imagination and innovation" as needed while saying there was a lack of "a spirit of communion" or working "as a team."

The Pope said, "We are therefore required, at this Christmas time and in all the time of our service and our existence – to live 'speaking the truth in love."

He said, "We are to grow up in every way into him who is the head, into Christ, from whom the whole body, joined and held together by every joint with which it is equipped, when each part is working properly, makes the body grow so that it builds itself up in love.'"

The BBC reported there was silence the end of Francis' speech.

The veteran Rome correspondent David Willey commented, "Clearly Pope Francis is meeting opposition among the nearly 3,000 strong staff of the Italian-dominated Curia.

"He had never worked in Rome before his election as pope last year, and - as a Vatican outsider from the other end of the world - is clearly frustrated by the slow-moving and creaking Vatican bureaucracy.

"He is trying to reform it with the help of a new group of cardinal advisers he has called in from every continent to draw up a new Vatican constitution."