Monsignor Krzysztof Charamsa, a Polish theologian, had worked at the Congregation of the Doctrine of the Faith, the Vatican's doctrinal arm, since 2003. He was also sacked from his jobs teaching theology at pontifical universities in Rome.

Charamsa, 43, told Italy's Corriere della Sera newspaper that he was gay and had a partner in an interview published on Saturday. The Church does not consider homosexuality a sin but priests, whether heterosexual or gay, are meant to be celibate.

Charasma also held a news conference with his partner and gay activists at a Rome restaurant. They had planned a demonstration in front of the Vatican but changed the venue several hours before it was due to have started.

The Vatican said the dismissal had nothing to do with Charasma's reflections on his personal life, which it said "merit respect".

But it said giving the interview and the planned demonstration was "grave and irresponsible" given their timing on the eve of a synod of bishops who will discuss family issues, including the Church's position on gays.

It said his actions would subject the synod, which Pope Francis is due to open on Sunday, to "undue media pressure".

At the news conference, Charamsa said he wanted to make "an enormous noise for the good of the Church" and apply "good Christian pressure" on the synod not to forget homosexual believers.

"This decision of mine to come out was a very personal one taken in a Catholic Church that is homophobic and very difficult and harsh (towards gays)," he said.

He suggested that a study be made of how many homosexuals work in the Vatican. "We can't continue showing contempt and offence towards homosexuals," he said.

The issue of homosexuality and the Church has dominated the aftermath of the pope's visit to the United States last week.

"I ask the pope to be strong and to remember us, homosexuals, lesbians, transsexuals and bisexuals as children of the Church and members of humanity," Charamsa said.

The Vatican has been embarrassed by a row over the pope's meeting during his U.S. trip with Kim Davis, a Kentucky county clerk who went to jail in September for refusing to honor a U.S. Supreme Court ruling and issue same-sex marriage licences.

**Editing by Louise Ireland