The Vatican has unveiled changes to its laws to name the sexual abuse of children as a specific crime and aim to implement international anti-money laundering norms as the city state seeks to end years of scandal.

Under the changes, child prostitution, sexual violence and sexual acts with children and child pornography will be included in a broader definition of the category of crimes against minors, the Vatican said in a statement.

Issuing a "Motu Proprio", a decree of his own initiative, Pope Francis also said he wanted to renew the Holy See's commitment to international conventions against crimes such as money laundering and terrorism.

The reforms extend the criminal liability of officials and staff of the Roman Curia, making it possible to indict them even for crimes committed outside the Vatican city state.

Francis, who succeeded Pope Benedict in March, has inherited a Church struggling to restore credibility after a series of scandals including the sexual abuse of children by priests and a money-laundering investigation of the Vatican's bank.

He has appointed an advisory board of cardinals from around the world to reform the Curia and has opened a special commission of inquiry to reform the Vatican bank.