Republican presidential candidate Donald TrumpDonald John TrumpWhite House counsel called Trump 'King Kong' behind his back: report Trump stays out of Arizona's ugly and costly GOP fight Trump claims he instructed White House counsel to cooperate with Mueller MORE slammed Mitt Romney during a rally on Thursday, bringing up a fundraiser Trump held for the 2012 GOP nominee.

"We had a fundraiser, and it was so big and it was raining out. I won't forget this one. It was raining, and really raining. It was a miserable, miserable day," Trump said

"And people came in, hundreds of people."

After the first fundraiser ended, Trump said the campaign called for another event because there were so many people attending.

"And because everybody's shoes were so wet, I ruined my carpet," he said. "This carpet was wiped out. And nobody thanked me for the carpet," he said.

"Maybe I can send Mitt a bill for carpet ruined."

During the rally, Trump brought up all of the help he gave Romney during his 2012 campaign. He called Romney a failed candidate who should have won the election but ran a horrible campaign.

Earlier Thursday, Romney bashed Trump, calling into question the front-runner's business successes and calling him a "phony" and a "fraud."