A Moscow court on Wednesday ordered the closure of Russia's oldest human rights organisation, the Moscow Helsinki Group, silencing another respected institution amid a political crackdown.
The judge of the Moscow City Court granted a justice ministry request to "dissolve" the rights group, the court said in a statement.
The Moscow Helsinki Group said it would appeal.
The decision is the latest in a series of legal rulings against organisations critical of the Kremlin, a trend that intensified after President Vladimir Putin sent troops into Ukraine last year.
The Moscow Helsinki Group was created in 1976 to monitor Soviet authorities' commitment to respect human rights and fundamental freedoms after the USSR signed on to a set of agreements on the last day of the Conference on Security and Cooperation in Europe in 1975.
But members of the group were jailed, harassed and expelled from the country and the Moscow Helsinki Group had to suspend operations in 1982 under pressure from Soviet authorities.
Its work was re-established by former political prisoners and rights activists during the perestroika movement -- a series of political and economic reforms -- in 1989.
- 'Life is long' -
The OSCE Office for Democratic Institutions and Human Rights (ODIHR) said the ruling was "contrary to the commitments made by all OSCE countries to respect the freedom to form and join associations".
ODIHR calls "on the Russian authorities to reconsider and reverse the decision", it said in a statement.
Roman Kiselyov, head of legal programmes at the organisation, said the Moscow Helsinki Group would continue its work but it was unclear what form it would take.
"Human rights work and the movement will not end there," Kiselyov told AFP.
"Decisions about the future will have to be made, that's for sure."
Genri Reznik, a star lawyer who defended the organisation in court, called the justice ministry's request to shut down the group a "legal disgrace".
He expressed hope however that courts in Russia could review the case in the future.
"Life is long," he told reporters.
"People will go, regimes will change."
For two decades, the organisation was headed by Lyudmila Alexeyeva, a Soviet-era dissident who became a symbol of resistance in Russia and who died in 2018.
When Alexeyeva -- the doyenne of Russia's rights movement -- celebrated her 90th birthday in 2017, Putin visited her at home, bringing her flowers.
"I am grateful to you for everything that you have done for a huge number of people in our country for many, many years," Putin told her at the time.
- 'Destruction' of symbols -
The justice ministry had accused the rights group of breaching its legal status by carrying out activities such as observing trials outside Moscow.
Before Putin sent troops to Ukraine, Russia dissolved another pillar of the country's rights movement, Memorial.
That group emerged as a symbol of hope during Russia's chaotic transition to democracy in the early 1990s and was co-awarded the Nobel Peace Prize less than a year after it was ordered to shut down.
Pavel Chikov, a prominent lawyer and activist, said the dissolution of top rights groups was equal to the "destruction" of Russia's intellectual and cultural institutions and symbols of "peace, progress, and human rights".
EU foreign policy chief Josep Borrell condemned the ruling, saying that Russian authorities were suppressing voices "rejecting authoritarianism and war".
"The Kremlin is extending its aggression in Ukraine into political repression at home," he said.
The Russian government has been using an array of laws to stifle critics of Moscow's offensive in Ukraine, imposing prison terms of up to 15 years for spreading "false information" about the military, among other measures.
Russia's top opposition politician Alexei Navalny is in jail and his political organisations have been declared extremist.
Most other key opposition figures are also either in prison or exiled.