Budapest (AFP) - Civil society groups in Hungary said Wednesday they have filed a challenge with the country's constitutional court against a law targeting foreign-funded organisations that critics argue is aimed at stifling anti-government dissent.
Under the June legislation, non-governmental organisations (NGOs) receiving more than 24,000 euros ($26,000) annually from a donor abroad must register as a "foreign-supported organisation" or risk closure.
They will also have to use the label "foreign-supported organisation" on their websites, press releases and other publications.
The tribunal must now rule on the bill's constitutionality which could lead to its annulment, although there is no deadline for the ruling which could take several months.
A total of 23 NGOs, including several human rights groups and anti-corruption bodies, sent the joint complaint Tuesday to the court protesting the "transparency" law.
The legislation is suitable "only for undermining the organisations' credibility and public trust in them", according to the document published online by several of the groups Wednesday.
"It infringes the good name of organisations... as well as the rights to freedom of speech and of association," it read.
Several organisations including the Hungarian Helsinki Committee (HHC) refugee rights group and the Hungarian Civil Liberties Union -- which co-drafted the petition -- say they will not comply with the new requirements.
HHC co-head Marta Pardavi told AFP she does not expect that the challenge will succeed.
"Sadly the court has been shy to deal with politically sensitive issues," she said.
The HHC also plans to continue legal challenges in Strasbourg at the human rights court, she added.
Any sanctions against NGOs will only be applied after May 2018, the deadline by which groups must submit a record of the previous year's donations.
The law, which has drawn international condemnation, is seen as marking an escalation in Prime Minister Viktor Orban's battle with Hungarian-born US billionaire George Soros, who funds many of the NGOs.
Orban has repeatedly accused the 87-year-old financier of orchestrating Europe's migration crisis and meddling in Hungarian politics.
"Pro-migrant Soros organisations do not want to be transparent", Balazs Hidveghi, a spokesman for the ruling Fidesz party, told the Hungarian news agency MTI Wednesday.