Israeli MPs have taken steps to outlaw the practice of "gay conversion" therapy by psychologists - the first Middle East country to do so.
A bill passed its first stage in parliament, after two parties in the coalition government joined the opposition to vote in favour.
Last year, Israel's then-education minister endorsed the therapy, triggering a backlash.
The bill risks a political crisis, with religious parties unhappy at the move.
After the vote, the ultra-Orthodox United Torah Judaism (UTJ), which is part of the fragile national unity government, threatened to introduce bills which the centrist Blue and White - also a member of the government - would find objectionable.
The bill must still pass two more readings before it becomes law.
The term "conversion therapy" refers to any form of treatment or psychotherapy which aims to change a person's sexual orientation or to suppress a person's gender identity.
The practice is widely opposed on logical, ethical and moral grounds.
Earlier this week, UK PM Boris Johnson called the supposed method "absolutely abhorrent", saying that plans to ban it in the UK would be brought forward.
'Born in sin'
Opposition Meretz party leader Nitzan Horowitz, who co-authored the bill, said its preliminary passage marked "historic change" in Israel.
Blue and White leader and Alternate Prime Minister Benny Gantz welcomed the result.
"Conversion therapy was born in sin and its place is outside of the law and the public norm," he tweeted.
"We will make sure that everyone, from every background and sexual orientation in Israel, has free choice and security over their identity."
Last year, then-Education Minister Rafi Peretz sparked outrage when he publicly condoned "gay conversion" therapy.
Prime Minister Benjamin Netanyahu called his remarks "unacceptable".
Israel has the most progressive attitude towards LGBTQ people in the Middle East, despite opposition from some conservative sections of society.
They are protected by anti-discrimination laws, have adoption and same-sex inheritance rights, and have been allowed to serve in the military since 1993.
The country has a record number of openly gay MPs and last year appointed its first openly gay minister.