The EU said Monday it was "very concerned" after Hungary's main opposition newspaper halted publication, sparking fears of a clampdown on press freedom by the right-wing government.
Left-leaning Nepszabadsag newspaper is to be sold, its editor said on Sunday, and while the publisher cited commercial reasons, activists and journalists blamed a tough environment created by Prime Minister Viktor Orban's government.
"The commission is aware of and concerned about the suspension of the publication of the Hungarian newspaper Nepszabadsag," said Margaritis Schinas, spokesman for the European Commission, the European Union executive.
"Questions have been raised on the reasons of the suspension," he told a briefing in Brussels. "We are following very closely, we are very concerned."
Schinas said media freedom and the protection of journalists were "at the very base of a free and democratic society".
The Commission added however that it was limited in what it could do in this case.
"The union's competencies in the field of media freedom and pluralism are limited," said spokeswoman Nathalie Vandystadt, adding that most media issues were governed by national and not EU law.
Orban's Fidesz party called the paper's suspension a "rational economic decision, not a political one", pointing to debts and a huge drop in sales.
But opposition parties, activists and journalists at the paper blamed the move on Orban's government cutting off oxygen for media that do not toe the government line.
They also said the timing was suspicious, coming a week after Nepszabadsag, which has often been critical of Orban, made corruption allegations against two close allies of the prime minister.
The small Democratic Coalition party announced Monday it would boycott parliament over the paper's suspension.
"The politically-driven closure of Nepszabadsag left the party with no choice," its leader Ferenc Gyurcsany, prime minister from 2004-9, told reporters in Budapest.
He said it was the "last straw" after Orban "lied" about the result of Hungary's October 2 referendum aimed at rejecting the EU's migrant quota plan.
Low turnout voided the vote but the government nonetheless declared victory and is seeking to change the constitution to ban the mass resettlement of refugees.
Orban's government has already been at loggerheads with the European Union over its rejection of quotas for sharing the burden of admitting migrants and for opening debate on reintroducing the death penalty.
"With its current policies, Hungary would not have been allowed to join EU in 2004," said Belgian ex-prime minister and senior MEP Guy Verhofstadt in a tweet Monday.