Former New York City Mayor Rudy Giuliani predicted Wednesday that when all is said and done, the controversy involving Hillary Clinton and the Clinton Foundation will be "bigger than Watergate."

Giuliani made the remarks while introducing Republican presidential nominee Donald Trump before a rally in Tampa Bay. He also argued that Richard Nixon Nixon wasn't as "shrewd" as the Clintons because he didn't destory the tapes that led to his resignation from the presidency.

"I am more than willing to predict that when the history of our day is written, the scandal you are watching unfold is going to be like the Teapot Dome scandal was in the 1920s, and maybe bigger — it's going to be bigger than Watergate," Giuliani told the crowd. "Nixon had to leave office and he did a lot of bad things, but it wasn't raking in millions and millions and millions of dollars through a phony charity."

"I'm not sure how much money was involved in the Teapot Dome, but I bet it couldn't have been too much more than the hundreds of millions of dollars the Clintons have been getting and turning the State Department into a pay for play operation," Giuliani said.

"Back in the '20s and in the Nixon era, well, you couldn't destroy emails 'cause there were no emails, and I guess Nixon just wasn't as shrewd as Hillary," the 2008 presidential candidate said. "He never destroyed those tapes. Nixon didn't destroy the tapes. He kept them. You know what the Clintons must be saying? What a jerk that Nixon was. You want to know how to really be a criminal? You destroy the evidence!"

Just prior, Giuliani railed against the Justice Department for not suggesting charges against Clinton, saying that he is "embarrassed" the department in which he once served did not treat her like a normal citizen.