LONDON — The British satellite broadcaster Sky warned on Tuesday that it may shut down its 24-hour news channel if the property becomes an obstacle to the company’s effort to sell itself to Rupert Murdoch’s 21st Century Fox.

In a regulatory filing with the Competition Markets Authority in Britain, Sky wrote that the regulator should not “simply assume the ‘continued provision of Sky News’” if ownership of the channel posed a problem for the $15 billion transaction.

The threat is an aggressive move by Sky to win approval of the transaction, which has been under review by the British government for nearly a year. In September, Britain’s culture minister, Karen Bradley, said that she intended to refer the proposed deal to the competition regulator.

Questions over the fate of the deal, in which 21st Century Fox would buy the 61 percent of Sky that it does not already own, have haunted it from the beginning. Mr. Murdoch is a divisive figure in Britain, and critics have questioned whether owning Sky would give his company too much power over British media, with stakes in television, newspaper and online outlets.

The bid by 21st Century Fox, a multinational media company based in New York, is rooted in the company’s effort to expand its global reach. Mr. Murdoch essentially created Sky in 1989, and the news channel was started the same year. Analysts have long believed that the media mogul would seek to take full control of the company.

The takeover of Sky would give 21st Century Fox control of a Pan-European satellite network, as well as rights to additional content such as broadcasts of the English Premier League and other soccer leagues in parts of Europe. It would also help the American company take on digital rivals like Netflix and Amazon, whose streaming services are increasingly being used by customers on mobile devices.

Mr. Murdoch tried to buy full control of Sky years ago, but that effort was abandoned as furor grew over a hacking scandal at the company, which was known then News Corporation. Since then, Mr. Murdoch split off 21st Century Fox from the rest of News Corp.

This past summer, Sky stopped broadcasting Fox News in Britain. 21st Century Fox said at the time that the move was made because the American news channel drew relatively few viewers, and not as a concession to British officials.

In June, Britain’s media regulator ruled that 21st Century Fox executives were “fit and proper” to hold broadcasting licenses in the country, while also concluding that a sexual harassment scandal at Fox News had amounted to “significant corporate failures.”

But the fate of the deal — and of the Murdoch media empire more broadly — was called into question on Monday, as media reports arose that 21st Century Fox had held preliminary talks with the Walt Disney Company about selling most of Fox’s assets, including its stake in Sky. Under the outlines of those discussions, which are not active at the moment, Mr. Murdoch would have sold everything except Fox News and their company’s local broadcasting and sports holdings.