The state of press freedom in Hungary has come under renewed scrutiny after the country’s main leftwing opposition newspaper was temporarily closed, ostensibly on commercial grounds.

The decision to suspend publication of Népszabadság by its owners, Mediaworks – who cited the need to seek a viable business model – sparked accusations of a “coup” from the paper’s journalists, many of whom learned of the closure only when they were denied entry to its newsroom in Budapest on Saturday.

About 2,000 demonstrators later gathered outside the national parliament to protest against the move.

Hungary’s rightwing prime minister, Viktor Orbán, who has voiced a desire to establish an “illiberal democracy”, has been repeatedly accused of interfering in the media.

Mediaworks, which gained total control of Népszabadság last year after buying out the Socialist party’s 27.7% stake, said the decision had been driven by plummeting sales and losses amounting to 5bn Hungarian florints (£14.8m) over the past decade.

“Népszabadság has lost 74% of its sold circulation in the past 10 years, corresponding to more than 100,000 copies,” the company said in a press release. The suspension would enable it to “focus on finding the best business model for the paper, in line with the current trends in the industry, and will start consultations in order to best secure future development,” the statement added.

But journalists dismissed the explanation as a smokescreen – pointing out that it came days after the paper disclosed corruption allegations against a minister in Orbán’s Fidesz party and a scandal embroiling the governor of the national bank.

Népszabadság had also criticised last Sunday’s referendum aimed at demonstrating public opposition to proposals to disperse refugees around EU member states, which overwhelmingly came out in favour of Orbán’s position but on too low a turnout to be valid.

“Of course they will try and paint this as a business decision but it’s not the truth,” one unnamed journalist told AFP. “Népszabadság was the largest group of quality journalists in Hungary trying to defend basic freedoms, democracy, freedom of speech, and tolerance.”

Even the far-right Jobbik party said the suspension was driven by politics. “The total undermining of Népszabadság is the latest example of Viktor’s Orbán’s megalomania. The only aim of Fidesz is to either gain 100% control over Hungarian media or to obstruct it,” its spokesman told AP.

Established in 1956, Népszabadság was controlled by the ruling communist regime until its collapse in 1989. The paper’s most recent sales figures were about 40,000, down from 270,000 two decades ago.