Minority rights advocates slammed the city government's decision, accusing it of giving in to right-wing nationalists. Parade organizers remained defiant, insisting they will gather somewhere.
The governor of Istanbul banned a gay pride parade scheduled for Sunday, citing concerns about the "security of citizens and tourists" and "public order" after an ultra-nationalist group threatened the march with violence.
It will be the second year in a row that the city's LBGT march, previously described as the largest in the Muslim world, has been blocked by city officials.
Last week, the ultra-nationalist Alperen Hearths group threatened to prevent the parade if the authorities didn't stop it. In response to that threat officials canceled the march.
The governor's emphasis on public safety and order distorted the image of a planned peaceful march, they said in an online statement headlined: "We are Marching, Get Used to It. We are Here, Not Going Away."
Organizers said they planned to gather in the city center Sunday despite the ban, insisting they had a right to a "peaceful gathering."
Amnesty International's Turkey expert Andrew Gardner said the government was using the "same tired, empty excuse" to ban a demonstration. Instead, he said, the government should offer security for the event so that it can go ahead.
Once a safe haven
Organizers said they may avoid Taksim Square, where widespread anti-government protests in 2013 were crushed by security forces. It has also been the site of periodic clashes between demonstrators and police in recent years.
Istanbul's gay pride parade has typically been a peaceful event, and the city has long been seen as a safe haven for members of the gay community across the Middle East.
In 2015, police broke up the parade with tear gas and a water cannon after organizers said they were refused permission because it coincided with the holy month of Ramadan.
Being gay in Turkey
Homosexuality isn't a crime in Turkey, unlike many other Muslim countries, but homophobia remains widespread. Critics accuse President Recep Tayyip Erdogan and his Islamist-rooted Justice and Development Party of showing little interest in expanding minority rights and being intolerant of dissent.
Turkey has been under a state of emergency since a failed coup attempt last July. The measure gives Erdogan's government sweeping powers, including allowing local authorities to ban demonstrations.
This year's planned parade coincides with the Eid al-Fitr holiday that marks the end of the Islamic holy month of Ramadan.