Republican presidential candidate Donald Trump speaks with University of Iowa football players before a campaign event at the University of Iowa Field House, Tuesday, Jan. 26, 2016 in Iowa City, Iowa.

MARSHALLTOWN, Iowa — Donald Trump on Tuesday bowed out of the final Republican presidential debate before the leadoff Iowa caucuses, saying Fox News moderator Megyn Kelly is “a lightweight.”

With 48 hours to go before the faceoff, campaign manager Corey Lewandowski confirmed Trump's decision Tuesday evening after a news conference in which Trump lashed out at Kelly and said she'd been “toying” with him.

“He will not be participating in the Fox News debate Thursday,” Lewandowski said immediately after the news conference.

Trump, who called his decision “pretty close to irrevocable” in the news conference, said he'd hold an Iowa event at the same time as the debate to raise money for wounded veterans.

“With me, they're dealing with somebody that's a little bit different. They can't toy with me like they toy with everybody else,” he said. “Let them have their debate and let's see how they do with the ratings.”

On Tuesday night's airing of her Fox News show, “The Kelly File,” Kelly said she'll be at the debate, which will “go on with or without Mr. Trump.”

In a statement released Tuesday night, a Fox News spokesman said Trump is still welcome to participate in the debate, but will not be allowed to “dictate the moderators or the questions.”

“Capitulating to politicians' ultimatums about a debate moderator violates all journalistic standards,” Fox said.

The Republican National Committee said the decision was up to Trump.