Thousands of people in the LGBT community and their supporters are fleeing the Mormon religion following a strict new policy that's forcing a wedge into families, according to observers. The Mormon church issued new rules in late 2015 not only barring LGBT partners but also banning their children from being baptised in the church.

The only way such children can become, or remain Mormon, is to denounce same-sex cohabitation and leave their families when they turn 18.

Since the rules were announced a flood of LGBT members and supporters have left the church, reports the Salt Lake Weekly.

Thousands of people have filed official church "resignation" papers and celebrated their Mormon liberation in public outdoor ceremonies in Salt Lake City, the heart of the Mormon community in America, according to Utah attorney Mark Naugle, who runs the website QuitMormon.com.

The church's policy against gays was launched after the right to same-sex marriage became the law of the land in the US.

Member exits aren't the only backlash against the church's policy. Brigham Young University in Utah, which is owned and operated by the Mormons, is coming under fire for its discriminatory policies.

The school recently applied to become part of the national Pac 12 athletic conference for universities. But LGBT advocates have written a letter to Pac 12 administrators saying a university with anti-gay policies, which breaks federal law, has no place in such an organisation.

"Currently, the Big 12 as a conference is overwhelmingly LGBT-inclusive," reads the letter from the pro-LGBT coalition Athlete Ally.

"BYU, conversely, actively and openly discriminates against its LGBT students and staff. It provides no protections for LGBT students. In fact, through its policies, BYU is very clear about its intent to discriminate against openly LGBT students, with sanctions that can include suspension or dismissal for being openly LGBT or in a same-sex relationship."

BYU athletic director Tom Holmoe immediately issued a statement on Twitter that the school welcomes "LGBT players, coaches and fans".

LGBT players, coaches and fans are always welcome to the BYU campus. Everyone should be treated with respect, dignity and love. Tom — Tom Holmoe (@TomHolmoe) August 9, 2016

But the school – and the Mormon church – do not welcome sexually active members of the LGBT community. Several self-described gay Mormon men proudly marry women and raise children boasting that they are "disavowing" their sexual preferences. But studies have shown that those relationship end overwhelmingly in divorce.

One twitter response to Holmoe noted: "So long as they don't actually act on their homosexuality right? You can 'be gay' but you can't BE gay?"

Mormon church officials argue that they are non-discriminatory since they are opposed to all pre-marital sex, whether it's heterosexual or homosexual. Yet since the church does not recognise same-sex marriage, gay sex is never condoned by the church. The church believes sex is proper only between a man and a woman who are married.

Brigham Young is also under investigation by the federal government for possible discrimination against women over how it handles sex assault complaints. When women have filed a sex assault complaint, they have become targets of investigations by Brigham Young University's Honour Code committee. The committee would probe why a woman, for example, might have been alone with a man in her room, and delving into a woman's sexual activity.