Celebrities including Greg James, Matt Lucas and Jack Whitehall have backed a campaign to save BBC Three, which is set to be axed as on-air channel.
As part of BBC plans to
An official announcement about the channel will be made on Thursday.
Stars have posted on social media using the hashtag #saveBBC3.
The response mirrors the campaign to save the digital radio station 6Music.
"I really hope reports that the BBC may kill BBC3 are just rumours. [Their] support of new comedy in particular is vital! #saveBBC3," wrote Whitehall, who writes and stars in Bad Education on the channel.
"Hearing horrible rumours about the possible closure of BBC3. This would be really bad for new comedy. Like, REALLY bad. #SaveBBC3," said Matt Lucas.
The comedian, who has launched a number of programmes on the channel, also posted a tweet repeating "#SaveBBC3" over and over again.
He added: "Little Britain, Gavin & Stacey, Torchwood, Being Human, Mighty Boosh, Pramface, Ideal - BBC3 is the home of new comedy & drama #SaveBBC3."
The director general of the BBC, Tony Hall, has said the organisation is "in the final stages of a budget process to find an extra £100m of savings" after cuts in funding.
He added: "Drama is one of the essences of the BBC and I want to make sure we are properly funded in that area.
"If that means taking hard decisions I am going to do that."
The BBC has released a statement in response to the campaign but refused to go in to details over cost-cutting plans.
"Tony Hall set out some of the very real challenges the BBC faces at his speech in Oxford," it read.
"He made clear that we will face tough choices about our budgets, and while nothing is off the table, no decisions have been made."
Since launching the campaign, the phrase #SaveBBC3 has trended on Twitter in the UK.
Richard Bacon, a BBC 5Live presenter, wrote: "BBC3 makes lots of great, clever, distinct programmes. If the rumours of it being cut are true, we might need to retool that 6Music campaign."
Meanwhile Radio 1 DJ Greg James, who has also featured on BBC Three programmes including Staying in with Greg and Russell, said: "Such a load of balls if the rumours about BBC3 being axed are true. Genuinely brilliant new comedy + live
"To name just 3 out of many: There wouldn't have been a launch pad for Gavin and Stacy, Bad Education or Little Britain without it #SaveBBC3,"
He added: "Not to mention the uninterrupted and unrivalled coverage of the big music festivals all summer. (not saying just coz I'm on it) #SaveBBC3."
Other famous faces, including Russell Kane, Rick Edwards and Jen Long have also leant their online support.
Austerity Britain, everybody. Let's sell off the NHS and cut Arts and BBC funding, that will make everything better. Not.
BBC 4 is also ~in danger~