VATICAN CITY (REUTERS) - Pope Francis has told the 19 men he plans to elevate to the rank of cardinal not to see their appointment as a promotion and not to waste money holding celebratory parties.

Pope Francis, who has made humility and poverty the hallmarks of his papacy and has warned against careerism in the Roman Catholic Church, announced on Sunday the names of the men, who come from 12 different nations.

In a letter to each of them which was released by the Vatican on Monday, the Argentinian-born pontiff said they should not let their appointment go to their heads.

"Being a cardinal does not mean a promotion or an honour or a decoration, it is simply a service," he said in the letter.

Pope Francis told them they should not react by doing anything that smacks of "high society or hold celebrations that have nothing to do with the gospel spirit of austerity, sobriety and poverty".

In the past, some prelates celebrated their elevation to the rank of cardinal with lavish receptions in their home dioceses or in Rome.

Pope Francis is leading by example. The former archbishop of Buenos Aires has renounced the spacious papal apartments in the Apostolic Palace used by his predecessors and lives is a small apartment in a Vatican guest house.

He uses the palace only to receive heads of state and to address crowds from a window overlooking St. Peter's Square.

Pope Francis has also given up the papal limousine and is driven around Rome in a Ford Focus, sometimes sitting in the front seat next to the driver.

The cardinals will be formally elevated to their new posts at a ceremony on February 22 known as a consistory.

Sixteen of them are under 80 and thus will have the right to vote for Pope Francis' eventual successor. The other three will be made cardinal emeritus, without voting rights, for their service to the Church.