"Serbia's government is effectively going against its own legal and constitutional protections for basic rights such as freedom of expression and freedom of assembly to all lesbian, gay, bisexual, and transgender people in Serbia," said John Dalhuisen, the group's director for Europe and Central Asia.
Serbian Prime Minister Ivica Dacic said in addition to banning the Gay Pride march, the government was barring a gathering of right-wing groups that planned to attack the event. It also canceled several national league soccer matches in Belgrade on Saturday because they often are attended by hooligans aligned with the extremists.
"We believe that at this moment Serbia does not need clashes and victims, and that's why we banned the gatherings," said Dacic, who is also the national police chief.
Opposition politicians said the ban showed that authorities are unable to protect freedom and human rights in Serbia.
"No democratic society has the right to retreat from the threats of violence against basic rights," said Liberal Party leader Cedomir Jovanovic.
Meanwhile, some 2,000 riot policemen were deployed Wednesday in front of an art exhibit in Belgrade organized by gay activists that the extremists had threatened to disrupt.
The reason? They claimed the photographs by a Swedish artist desecrated the image of Jesus Christ.