Pope Francis has ordered cardinals to take a 10 per cent pay cut and reduced the salaries of most other clerics working in the Vatican in order to save jobs of employees as the coronavirus pandemic has hit the Holy See's income.
The Vatican said on Wednesday that Francis issued a decree introducing proportional cuts starting on April 1.
A spokesman said most lay employees would not be affected by the cuts.
Francis has often insisted that he does not want to fire people in difficult economic times, even as the Vatican continues to run up deficits.
Cardinals who work at the Vatican and live there or in Rome are believed to get salaries of about 4000-5000 euros ($A6,215-$A7,765) a month, and many live in large apartments at well below market rents.
Most priests and nuns who work in Vatican departments live in religious communities in Rome such as seminaries, convents, parishes, universities and schools - giving them greater protection from economic downturns.
They have much lower living expenses than lay employees - such as police, ushers, firefighters, cleaners, art restorers and maintenance personnel - who live in Rome and many of whom have families.
It is these lay workers who the pontiff appeared to want to protect, as most of their employment levels were not listed in the papal decree.
Apart from the cardinals, other clerics will see their salaries reduced by between 3 per cent and 8 per cent.
Programmed pay rises will be suspended until March 2023.
The provisions will also apply to senior staff of other papal basilicas besides St Peter's in the Vatican.
The Vatican's top economic official said earlier this month that the Holy See, the central administrative body of the worldwide Catholic Church, may have to use 40 million euros ($A62 million) in reserves for the second straight year as the COVID-19 pandemic burns through its finances.
It expects a deficit of about 50 million euros this year.
Revenues are expected to be about 213 million euros in 2021, down 30 per cent over 2020.
St. Peter's Basilica and the Vatican Museums, the latter a cash cow that received about 6 million paying visitors in 2019, were closed or only partially open for much of 2020 because of the pandemic.
The museums had been due to reopen this month but remained closed because of a new lockdown by Italy.
In a seven-point preface to the decree explaining why action was needed now, Francis said the pandemic "has negatively affected all the sources of income of the Holy See and the State of Vatican City".
The Holy See budget covers entities in Rome that oversee the governing of the 1.3 billion-member worldwide Church, its diplomatic representations and media operations.
The Holy See's income is from donations, real estate management and investments.