According to a March 20 New York Times column, NBC's Chuck Todd told The Times' Jim Rutenberg that he “will no longer allow Mr. Trump to do prescheduled interviews by phone.” Rutenberg noted that Fox's Chris Wallace has also refused to allow Trump to phone in. From the article:

Then there are the Sunday morning public affairs programs. For decades they have served as proving grounds where candidates must show up on camera, ideally in person, to handle questions without aides slipping them notes, their facial reactions and body language on full display. It's why the programs were named “Face the Nation” and “Meet the Press” -- not “Call the Nation” or “Phone the Press.”

And yet, as the campaign began in earnest, all of the shows went along with Mr. Trump's insistence that he “appear” by phone -- all except one, “Fox News Sunday With Chris Wallace.”

“I just thought even if we took a ratings hit -- and to some degree we did -- it was a line worth holding,” Mr. Wallace told me.

On Friday, Chuck Todd, the moderator of “Meet the Press,” told me he had only grudgingly allowed Mr. Trump to call in to his show earlier in the campaign, determining that he would rather have Mr. Trump take questions via phone than not at all.

Now, Mr. Todd said, he will no longer allow Mr. Trump to do prescheduled interviews by phone on the NBC program. And CNN told me it would think twice before giving full coverage to a Trump news conference that devolves into an infomercial.