WARSAW — The largest pride parade in central and Eastern Europe was expected to bring thousands of people to the streets of Warsaw on Saturday, at a time when the gay rights movement in Poland is under siege by hate speech and a government campaign depicting it as a threat to families and society.

While many Poles in Warsaw and other cities have grown increasingly supportive of the rights of lesbians, gay men, and bisexual and transgender people, a backlash is underway. In recent months, officials from the right-wing governing party, Law and Justice, have portrayed the rights movement, particularly calls for sex education stressing tolerance, as a threat to families and children.

Poland is to have 20 pride parades this year, a record number. In some cases, even centrist and left-wing mayors have tried to ban them, usually citing security concerns.

WARSAW — The largest pride parade in central and Eastern Europe was expected to bring thousands of people to the streets of Warsaw on Saturday, at a time when the gay rights movement in Poland is under siege by hate speech and a government campaign depicting it as a threat to families and society.

“Last month, a transgender girl killed herself by jumping from a bridge in Warsaw. When a group went later with a rainbow flag to the bridge to honor her, its members were assaulted.”

While many Poles in Warsaw and other cities have grown increasingly supportive of the rights of lesbians, gay men, and bisexual and transgender people, a backlash is underway. In recent months, officials from the right-wing governing party, Law and Justice, have portrayed the rights movement, particularly calls for sex education stressing tolerance, as a threat to families and children.

Poland is to have 20 pride parades this year, a record number. In some cases, even centrist and left-wing mayors have tried to ban them, usually citing security concerns.

The Law and Justice leader, Jaroslaw Kaczynski, recently called the gay rights movement a foreign import that threatens the nation’s identity. In conservative areas, town councils have been declaring their municipalities “L.G.B.T. free.”

On the eve of the parade, a far-right journalist on public television, Rafal Ziemkiewicz, sent chills down the spines of the L.G.B.T. community with a Twitter post. “One must shoot at L.G.B.T.” people he wrote, before adding, “Not in the literal sense of course — but these are not people of good will or defenders of anybody’s rights, (the movement is) a new mutation of Bolsheviks and Nazis.” Read more via New York Times