Staff at Sky News have piled into the debate over the broadcaster's potential takeover, warning the competition watchdog that blocking the deal would trigger 500 job losses and deliver a "deeply damaging" blow to British journalism.
The group has told the Competition and Markets Authority (CMA) that the closure of the channel would "damage media plurality" in the UK by leaving the BBC as the only provider of 24-hour news.
The move comes after Sky said it would shut down Sky News if it proved the main barrier standing in the way of 21st Century Fox's £11.7 billion bid to buy the remaining 61% of the broadcaster it does not already own.
The deal is currently being scrutinised by the competition watchdog on the grounds of media plurality and broadcasting standards.
The letter addressed to CMA case officer Sabrina Basran has been signed by 175 staff, including All Out Politics presenter Adam Boulton, business presenter Ian King and special news correspondent Alex Crawford.
The group wrote: "We are a group of 175 Sky News employees who have decided to write to you as an interested party in the 21st Century Fox/Sky merger.
"We have serious concerns about what the potential closure of Sky News would mean not only for us, but for wider society. In the first instance, scrapping the channel would result in redundancy for more than 500 people.
"The loss of those jobs would be deeply damaging for journalism in the UK."
It comes after the attempted takeover of Sky took a fresh twist on Thursday when Fox announced the sale of its entertainment assets to Walt Disney in a 52.4 billion dollar (£39 billion) deal that includes its stake in Sky.
As part of the announcement, Fox stressed it would press ahead with attempts to buy the 61% of broadcaster Sky it does not already own before the Disney deal closes in 12 to 18 months' time.
It means Disney could potentially take full control of Sky and Sky News. The entertainment giant's chairman and chief executive Bob Iger told Bloomberg TV at the time that "all of Sky has a future".
The letter added: "The closure of Sky News would damage media plurality in this country because we would only have the BBC for domestic 24-hour television news. There would, therefore, be less diversity of independent views, with one broadcaster enjoying a monopoly.
"All of us at Sky News have a genuine commitment to broadcasting standards. We are proud of our excellent track record of compliance."