Index is among a handful of independent outlets whose finances and freedom to operate have been curtailed by Prime Minister Viktor Orban's efforts to control more of Hungary's media.
Hungary's leading online news website says its editorial staff and independence are at risk from what it calls "outside interference".
Index.hu has moved its "independence barometer" it set up in 2018 to "in danger" from "independent", adding that it staff and independence are "in grave danger".
"Index is under such external pressure that could spell out the end of our editorial staff as we know it. We are concerned that with the proposed organisational overhaul, we will lose those values that made Index.hu the biggest and most-read news site in Hungary," its editor-in-chief Szabolcs Dull says in a statement signed by nearly 90 employees.
Index is among a handful of independent outlets whose finances and freedom to operate have been curtailed by Prime Minister Viktor Orban's efforts to control more of Hungary's media. In recent years most have come under the control of government or pro-government business figures.
The statement does not give more details but said "the next couple of days will determine the fate of Index".
The site set up its barometer in 2018 following a change in the ownership of companies that handle its advertising and provide its IT services. At the time, Index said it believed that safeguards meant its editorial independence would not be compromised. But it added that if that changed, "we will notify the world as loud as we possibly can".
Euronews' Budapest office understands from sources among the Index staff that "the situation is unclear but serious".
Another independent Hungarian news site, 24.hu, said on Sunday that sections of Index would be outsourced to external companies, meaning the newsroom would effectively be dismantled.
Index executive Laszlo Bodolai told Media1.hu, a website specialising in media matters, that while a plan had been drawn up for a possible reorganisation, it had been rejected by the news site’s management.
In late March a businessman linked to the pro-government transformation of Hungarian media, Miklos Vaszily, said that he had acquired a 50% stake in the company which sells Index's advertising.
Under his tenure, another site Origo.hu changed from an independent news outlet to an openly pro-government operation.
In recent years several publications have been shut down because of Orban's moves to increase the prime minister's media dominance and that of his Fidesz party. They include the left-wing daily Nepszabadsag and Heti Valasz, a conservative weekly.
The European Parliament and European Commission have accused Orban of threatening the rule of law by stamping party control over the judiciary, media and academic institutions.
In its 2020 global survey of media freedom by Reporters Without Borders, Hungary fell two places to 89th out of 180 countries. In 2013 it was in 56th place.
The report said the pro-government media foundation KESMA "dominates the media landscape, and market distortion of state advertising to media is still going on".