Francis used his annual Christmas greetings to the Roman Catholic Church’s central bureaucracy, or Curia, to urge top officials to be more willing to welcome change.
To a muted Apostolic Palace, Francis said: “Reforming Rome is like cleaning the Sphinx of Egypt with a toothbrush.
“You need patience, dedication and delicacy.”
The Pope, in his Christmas message to staff, acknowledged there were good, competent and loyal people working in the Vatican but said others were either incapable or unwilling to consider reforms.
When these people were “delicately” removed, Francis said, “they falsely declare themselves martyrs of the system, of an ‘uninformed pope’ or the ‘old guard’, when in fact they should have done a mea culpa.”
Francis said some in the bureaucracy – the nerve centre of the 1.2-billion-member Church and whose members are entrusted with carrying out the Pope’s decisions – were part of “cliques and plots”.
Francis called this “unbalanced and degenerate” and a “cancer that leads to a self-referential attitude”.
Since his election as the first Latin American Pope in 2013, Francis has put reforming the Italian-dominated Curia high on his agenda in a bid to bring the Church’s hierarchy closer to its members.
He is also keen to overhaul its finances and turn over a new leaf following the scandals that dominated the pontificate of his predecessor, Benedict.
However, his plans have been met with resistance. On Thursday, Francis spoke of “traitors of trust” who had been tasked with reform but “let themselves be corrupted by ambition and vanity”.
Earlier this month, Pope Francis called for the Lord’s Prayer to be changed – arguing the translation used by many parts of the world goes against the teachings of the Bible.
The Lord’s Prayer is spoken by the majority of the world’s 2.2billion Christians, and is cited by the Bible as the way Jesus taught his disciples to pray.
However Pope Francis has argued the Italian – and indeed the English translation – go against the teachings of the church.
In the much-recited prayer, followers of the faith call on God to “lead us not into temptation, but deliver us from evil”.
Speaking to Italian broadcasters, the Pope argued this was incorrect.
He said: “It is not a good translation because it speaks of a God who induces temptation.”
He added Christians in France had adapted the prayer to get around the issue.
Pope Francis said: “The French have modified the prayer to ‘do not let me fall into temptation’, because it is me who falls, not the Lord who tempts me to then see how I fall”.
Last month the head of the Catholic church admitted he had – from time to time – fallen asleep during prayer.