Facebook has been forced to issue an assurance to media publishers that a potentially damaging change to news feeds being tested in a handful of countries will not be rolled out globally.
The controversial change splits a users news feed in two, separating posts made by family and friends from that of content from publishers and websites which they follow, putting the latter into a tab called explore.
Media has raised concerns that removing their content from the main feed could reduce its reach. Many companies rely on Facebook to drive a large amount of traffic to their websites.
Facebook's head of news feed Adam Mosseri said: "The goal of this test is to understand if people prefer to have separate places for personal and public content.
"We will hear what people say about the experience to understand if it’s an idea worth pursuing any further. There is no current plan to roll this out beyond these test countries or to charge pages on Facebook to pay for all their distribution in news feed or explore."
The explore tab is a new feature that is being introduced globally, but in every other country it includes news sources that a user does not follow.
The changes were first brought to light by a journalist in Slovakia, one of the countries the experiment is taking place along with Sri Lanka, Bolivia, Serbia, Guatemala and Cambodia, who identified a drop in interactions.
The row shows the danger of relying on tech platforms, said Charlie Beckett, a former journalist and media professor at the London School of Economics but, "clearly Facebook is experimenting with all kinds of ways of shaping news content flows, including methods of promoting 'quality' or credible content".
However, there are greater concerns more broadly.
"I am more worried about changes that we don't know about and the general lack of clarity about the principles behind their trials. It's a period where Facebook is in flux and it is in the public interest, as well as the interest of the news media industry, that they are transparent and accountable to the wider impact of what they do," he said.
Media faces declining print revenues and challenges making up losses from online advertising, leaving many feeling they are at the mercy of the tech company's distribution platforms, their algorithms and any changes they make.
Facebook and other tech platforms have found themselves under greater scrutiny in light of the issue of fake news, their role in policing dangerous content and deeper concern that they are actively being exploited. Executives from Facebook, Google and Twitter will next week face US Congress to answer questions over how their platforms were used by Russia during last year's election.