(CNN) -- The broadcast networks are deliberating over President Donald Trump's request for airtime to deliver a prime time address on border security, network executives told CNN.

Trump announced in a tweet on Monday that he will deliver his address at 9 p.m. ET on Tuesday. In his tweet, the president characterized the situation on the border as a "national security crisis."

For several hours on Monday, none of the major broadcasters said they had committed to airing what is sure to be a highly controversial address. Network newsrooms were abuzz with speculation about what the broadcasters would decide.

Come Monday evening, CBS said it would go ahead and carry the address. ABC, NBC, PBS, and the Fox broadcast network have yet to comment.

Presidents have been using Oval Office addresses on broadcast networks to make big announcements for decades. But the networks sometimes resist requests for air time for a variety of reasons, including the perceived urgency of the subject and the popularity of the shows that would be interrupted.

With Trump, there are other factors to consider, including his record of deception and his tendency to ramble off script in long speeches.

Many Trump critics posted messages on social media urging the networks not to air an address that could be filled with falsehoods. Some said that a prominent Democrat should be given equal time. It is unclear if any sort of Democratic rebuttal is in the works.

Spokespeople for ABC, NBC, the Fox broadcast network, and PBS either declined to comment or said they would comment at a later time.

One of the TV executives who spoke to CNN Business confirmed that the White House had requested time for the speech, as is customary in the relationship between a president and the press.

"Time has been requested for 9 p.m. Networks are deliberating," the network executive said.

Trump is almost certain to go ahead with the address regardless of what the broadcast networks do.

Spokespeople for CNN and Fox News said their networks would air the address. A spokesman for MSNBC said the channel's coverage plans were "still being discussed." It would be highly unusual for the cable news networks not to air a presidential prime time address.

There is precedent, however, for broadcast networks declining to air a presidential speech. In 2014, ABC, NBC, and CBS declined to carry an address delivered by President Barack Obama on immigration, though Obama's White House never formally requested time after it was determined networks would be reluctant to agree to broadcast it.

Trump's Monday request for networks to air his speech touched on a number of debates that have been raging in journalism since his ascension to the Oval Office. Among them: Should his fact-free speeches be aired live? What kind of fact-checking methods should networks employ?

There has been a recent debate in journalism circles about whether networks should air Trump's words in real-time. Several media critics, for instance, told CNN last week that networks should not rush to air Trump's remarks made during pool sprays and briefings, given how much misinformation he spreads.

"Some advice -- demand to see the text in advance and if it is not truthful either don't air it or fact check it live on lower third," tweeted Joe Lockhart, the former White House press secretary under President Bill Clinton. "And cut away if he goes off text and starts lying."