'Don't Say Gay': Biden denounces 'hateful' new Florida bill

US President Joe Biden has condemned a Florida bill that would ban discussion of sexual orientation in primary schools as "hateful" to LGBT students.

Governor Ron DeSantis has signalled his backing for the measure and it appears to have enough support to pass through the state's Republican-led legislature.

Activists have dubbed it the "Don't Say Gay" bill and warn it will stigmatise LGBT people and issues.

But its proponents say the legislation is about protecting parental rights.

The proposal was introduced in the state House of Representatives last month. An identical version advanced in the state Senate on Tuesday.

In a Twitter message to the LGBT community - "especially the kids who will be impacted by this hateful bill" - Mr Biden vowed to "continue to fight for the protections and safety you deserve".

At a news conference earlier, White House press secretary Jen Psaki said: "Every parent hopes that our leaders will ensure their children's safety, protection, and freedom.

"Today, conservative politicians in Florida rejected those basic values by advancing legislation that is designed to target and attack the kids who need support the most."

State laws that ban or constrain the discussion of LGBT life in classrooms - sometimes referred to as "no promo homo" laws - are not uncommon.

Several were introduced in the 1970s and 1980s, closely correlated with anti-gay rights activism at the time, but many have long been repealed.

Currently, four US states - Louisiana, Mississippi, Oklahoma and Texas - have laws on the books that expressly prohibit or limit sex education to heterosexual activity.

Last year, Tennessee and Montana passed laws that allow parents to opt their children out of discussions on sexual orientation and gender identity.

The Florida bill goes a step further, allowing parents to directly sue schools districts and seek damages if they believe an educator has broken the law.

Although the ban will in theory apply largely to sex education courses at the primary grade levels, it also calls on school districts to avoid LGBT topics when "not age-appropriate or developmentally appropriate for students".

Echoing the text of the bill, Governor DeSantis, a Republican widely touted as a possible 2024 White House contender, said schools should avoid "entirely inappropriate" topics and instead be teaching science, history, civics and other lessons.

"The larger issue with all of this is parents must have a seat at the table when it comes to what's going on in their schools," he told reporters on Monday.

But LGBT advocates have warned the legislation will harm the mental health of LGBT youth and undermine their existing protections under the law while moving Floridians away from a more inclusive school environment.