Billy Bush has been suspended from the "Today" show "pending further review of the matter."

It is unclear if he will ever return to the broadcast.

"He will never be on the show again," an on-air source said Sunday night, reflecting what staffers are saying behind the scenes.

A second source at the network confirmed Monday that his return is unlikely.

"Today" co-host Savannah Guthrie briefly told viewers about Bush's suspension on Monday morning.

The sudden change came amid a chorus of calls for disciplinary action against Bush over his vulgar 2005 conversation with Donald Trump that was caught on tape and revealed on Friday.

"He's suspended or perhaps fired for what he said. The other guy's running, still, to be the head of the free world," CNN media analyst Bill Carter said on Monday's "New Day."

NBC sources initially said Bush was not being disciplined and that he would be in his usual spot as co-host of the "Today" show's 9 a.m. hour on Monday morning.

As late as Sunday morning, one of the sources was saying that Bush would use Monday's broadcast to reiterate the apology he made Friday.

But on Sunday afternoon, senior NBC executives made the decision to bench Bush on Monday, effectively reprimanding him.

A couple of hours later, the executive in charge of "Today," Noah Oppenheim, said in an internal memo that the executives had decided to go even further and suspend Bush.

"I know we've all been deeply troubled by the revelations of the past 48 hours," Oppenheim wrote.

"Let me be clear -- there is simply no excuse for Billy's language and behavior on that tape," he wrote. "NBC has decided to suspend Billy, pending further review of this matter."

Before the memo was released, the on-air source said staffers were in the dark, stuck refreshing Twitter to find out what was going on with Bush.

The suspension was a stunning turn of events. The "Today" show recently made a multi-million-dollar bet on Bush, relocating him from Los Angeles to New York and making him a co-host.

But the taped 2005 conversation between Bush and Trump has upended the careers of both men.

Trump's vulgar and aggressive comments about women, alluding to sexual assault, caused some Republican leaders to retract their endorsements of him.

Bush played along and joked with Trump, even while Trump talked about trying to sleep with one of Bush's colleagues.

At the time the video was recorded, Bush was a co-host of NBC's entertainment show "Access Hollywood." Now he is a key player on the "Today" show, the profit engine of NBC News. Until Friday, some observers believed he was being groomed to take over for Matt Lauer someday.

Related: Billy Bush: The other voice in the Donald Trump video

Bush is a cousin of both former President George W. Bush and 2016 Trump opponent Jeb Bush.

Bush issued a forthright apology statement on Friday, but it did not quiet the calls for action by NBC. There was an online petition circulating that calls for his firing, and there are hundreds of outraged comments on the "Today" show's social media pages.

On top of that, as Anthony Quintano -- who formerly ran the "Today" show's social media efforts -- pointed out on Friday, "a majority of the 'Today' show production staff is female." It "won't go over well internally to keep Billy Bush around," Quintano said in a tweet.

Bush's 9 a.m. hour is heavy with lifestyle fare, with less political news than the earlier hours. Still, it is a product of NBC News, so the news division has ethical considerations to make about Bush's role in the tape -- and in ongoing coverage of the election.

Decisions about releasing the "Access Hollywood" tape reached to the highest level of NBCUniversal, to the office of CEO Steve Burke, the Wall Street Journal reported on Sunday.

An NBC source confirmed Burke's involvement and reiterated that the network was preparing to broadcast a report about the tape when it was leaked to the Washington Post on Friday.

Related: How the shocking hot mic tape of Donald Trump was exposed

Adding a slightly bizarre element to the story, the New York Times reported Sunday that the outgoing voicemail message on Bush's extension at NBC says, "You've reached Billy Bush's office, he's busy making America great again, please leave a message." The voice is apparently not his.