Faithful attend the Easter mass led by Pope Francis in Saint Peter's Square at the Vatican

In what some say is an "unprecedented" move, the Vatican lodged a diplomatic protest against an Italian bill that would penalize discrimination and hate speech based on sexual orientation and gender identity.

According to Agence France Press Tuesday, draft legislation known as the Zan law being considered in the Italian Parliament has received a rebuke from the Holy See.

The Vatican argued in a letter that the proposed law violates the Concordat, the bilateral treaty between the city-state and the nation of Italy, because it curtails the freedom of Catholics to hold and express their beliefs.

The Vatican letter, called a "note verbale," was "informally delivered" to the Italian ambassador on Thursday, Vatican spokesman Matteo Bruni told AFP.

"It is an unprecedented act in the history of relations between the two states — or at least, there are no public precedents," the Corriere della Sera newspaper reported. The Italian daily noted that the letter was presented by Archbishop Paul Richard Gallagher, the Vatican's de facto foreign minister.

Some are concerned that Catholics may face legal consequences for expressing religious views on LGBT issues if the law passes. The Vatican's letter cited the Holy See's objection to Catholic schools not being exempted from a proposed national day against homophobia and transphobia designated for May 17.

The letter argued that the bill threatens the Vatican's "freedom of organisation" and "freedom of thought"

Supporters of the bill say the Vatican's stance is off-base and is an attempt to interfere in Italy's politics.

"The text [of the law] does not restrict in any way freedom of expression or religious freedom," tweeted Alessandro Zan, the gay, center-left lawmaker who is sponsoring the bill. "And it respects the autonomy of all schools."

In another tweet, Zan said that "there can be no foreign interference in the prerogatives of a sovereign parliament."

Roberto Grendene, secretary of the Union of Atheists and Agnostic Rationalists, said in a statement shared with The Associated Press that the Italian government has the "political and moral obligation to not only just resist pressure but to unilaterally denounce this unprecedented interference in state affairs."

Those who oppose the Zan law, such as former deputy prime minister and right-wing Lega Nord party leader Matteo Salvini, argue the legislation amounts to LGBT propaganda in schools. Salvini contends such a law will lead to censorship and trials "for those who believe that mum, dad and family are the heart of our society."

Cerriere reports this is the first time the Vatican has entered the political fray through the Concordat, which grants the city-state the right to protest in this way.

Although the Roman Catholic Church is officially opposed to homosexuality in its cathechism, the Vatican did not make a move of this kind when the Italian Parliament passed legislation on same-sex unions in 2016. The Zan law is expected to face pushback in the Senate. And if lawmakers were to revise the bill, it would have to return to the lower house, which passed the bill in November.

While Pope Francis is often portrayed as more liberal on LGBT issues, the head of the Church has spoken out from time to time about the dangers of gender ideology.

In an interview between Francis and a priest published last year, the pope decried "gender theory" was an area where he sees evil at work in the world. The pontiff called it a "dangerous" goal that seeks to "destroy at its roots" the plan of God for humanity, Crux reported Tuesday.

"Diversity, distinction. It would make everything homogenous, neutral. It is an attack on difference, on the creativity of God and on men and women," the pope said at the time.

In March, the Vatican's Congregation for the Doctrine of the Faith issued a formal response to a question about whether Catholic churches have the power to bless same-sex unions by stating that churches can't bless same-sex marriages since God "cannot bless sin."

Additionally, the Vatican's Congregation for Catholic Education issued a document in 2019 titled "Male and Female he Created Them," which pushed back against "calls for public recognition of the right to choose one's gender, and of a plurality of new types of unions."

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