4: 15 p.m. ET UPDATE: Mitt Romney tells Fox News he informed Donald Trump he won't participate in Dec. 27 debate. 

Looks like the Donald Trump-Jon Huntsman feud won't be over anytime soon -- especially on the question of whether the Republican presidential candidate tried to meet with the real estate mogul to seek his endorsement.

"I called his office one time," Huntsman told NBC on Tuesday, "when he got out of the race -- as I did Tim Pawlenty -- just as a gesture of kindness."

But Trump says Huntsman was looking for more.

"Every candidate, virtually, has come up to my office, and they don't want my money -- they want my endorsement," Trump said on Fox and Friends Tuesday.  "He asked to come and see me. And I said, you know -- really, I just sort of turned him down in a very nice way, and now, all of a sudden, look what happens."

Huntsman also made his feelings clear on the upcoming Trump-moderated presidential debate, calling the idea "a joke."

"The presidency of the United States of America is beyond reality shows," he told NBC.  "So, you'll have two or three people go on, and then Mr. Trump will weigh in after in terms of who he thinks he'll want to support? This is about politics as show business."

Click here to see Huntsman on Monday's America's Newsroom.

"He's not in the debate because his ratings are so low," Trump fired back, referring to a candidate forum on Fox News' "Huckabee" over the weekend, in which Huntsman did not participate. "I mean, he has just such low polling numbers that he was canceled out of Saturday night's debate."

Trump, who's hosting the debate on Dec. 27 with Newsmax and ION Television -- just one week before the Jan. 3 Iowa caucuses, has received a "yes" to attend from candidates Newt Gingrich and Rick Santorum. Huntsman and Ron Paul have said they will not attend while others are still mulling a decision.

Trump claims his debate will be a ratings bonanza, and consequently, a valuable vehicle for the candidates.

"We're going to have a real debate," he said. "It'll be some good entertainment, which I don't want to say, but you still need it. But more importantly, we're going to get some of the issues out that are important."

But not everyone is swayed by Trump's would-be kingmaking prowess. Arizona Sen. John McCain, the 2008 Republican presidential nominee, said he thought the candidates are so preoccupied with attending debates they are losing focus on their races. He said the Trump debate won't add to the objective of getting nominated.

"It's their decision, but I do think that on Dec. 27, on an obscure network, I wonder if that is the best use of the candidates’ time. I think they should be resting up over Christmas and the next few days and be ready to go right after the first of January,” McCain told Fox News.

And while pundits like Fox News contributor Karl Rove have criticized the debate, Trump said Tuesday the controversy is only helping his cause.

"All these guys are just making the debate hotter," Trump said. "We will get, probably, the highest ratings of any debate they've had because of all this controversy. It's a good thing. It's not a bad thing."

Trump has reveled in the controversy surrounding his role in the presidential nonimating process, further fueled by his suggesting that he could enter, (or re-enter) the race if he's dissatisfied with the field.

But voters will have to wait at least until after the Dec. 27 debate for Trump to make up his mind.

"After the debate, I'm going to endorse somebody," Trump told Fox News' Sean Hannity on Monday, adding that he hasn't completely ruled out his own third-party run.

"I think there's a big force of people out there that are tired of Republicans and Democrats," he said.

But Trump did say he was taken with several candidates, and impressed Gingrich's rise in the polls.

"He's like a rocket ship," Trump said. "I've never seen anything like it."