His advice came when he paid homage to father Giuseppe Puglisi who was shot dead by the mafia in Sicily 25 years ago.

The pope warned the "brothers and sisters" that they could not "believe in god and be Mafiosi" - a reference to the fact that many mafia members are regular worshippers.

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The pope addressed the faithful at Palermo’s piazza Europa and will later visit Puglisi’s parish in the working-class neighborhood of Brancaccio.

The priest was renowned for working with young people to keep them away from drugs and the mafia.

The pope said Sicily needed "men and women of love, not men and women 'of honour'", referring to the code mobsters use to define themselves.

According to the pope "a person who is a mafioso does not live as a Christian because with his life he blasphemes against the name of god.

Father Puglisi was shot dead on the doorstep of his home on his birthday, 15 September, in 1993.

His murder came at a time when mafia violence against opponents of their influence was of particularly grave concern.

Puglisi was declared a "martyr" who was "killed by hatred of the faith" by Pope Francis' predecessor Benedict xvi in 2012.