Pope Francis has named a special envoy to prioritise spirituality at the Roman Catholic shrine at Lourdes in France over "managerial and financial" aspects.

The Italian press said Friday that the nomination of Lille auxiliary Bishop Antoine Herouard is seen as the equivalent of placing the holy spring in the foothills of the Pyrenees mountains under supervision.

Lourdes is one of the most revered sites for the world's 1.2 billion Catholics because the town is said to be where the Virgin Mary appeared to a peasant girl in a grotto.

"Pope Francis, who has this case very much at heart, wishes to accentuate the spiritual primacy over the temptation to overemphasise the managerial and financial aspect," the official Vatican News website said.

The pope wants centres of Marian devotion to be "ever more a place of prayer and of Christian witness corresponding to the needs of the People of God."

A former Renault manager, Guillaume de Vuilpan, was put in charge of Lourdes in 2017, and has introduced new products at the site.

The shrine returned to profit in 2018 after 10 years in the red, accumulating losses of €10 million.

Last year, 1.2 million pilgrims visited the site, half of them on organised tours.