There's a "very big difference" between running a public company like Starbucks and a private company like the Trump Organization, Howard Schultz told CNBC on Tuesday, as speculation swirled around whether he might run for the White House in 2020.

The outgoing Starbucks' executive chairman and former two-time CEO drew what he considers a distinction between his past experience running the coffee giant and President Donald Trump's time leading his namesake company.

"When you are talking about a 'CEO' in terms of public office, there is a very big difference between someone who has run a [public] global enterprise like myself … versus someone who has run a private company with very little fiduciary responsibility to other shareholders," Schultz said on "Squawk Box."

"I want to say this respectfully so no one misunderstands what I'm about to say, but there is a bifurcation," said Schultz, who supported Democrat Hillary Clinton over Trump in the 2016 presidential election. "I'm not saying that as good or bad, but it's a big difference."

The Trump Organization reportedly had more than 22,000 employees, with revenue of $9.5 billion in 2016. Starbucks has more than 330,000 employees and more than 28,000 locations worldwide, with a market capitalization of $76.8 billion. The coffee giant reported revenue of $6.03 billion for the quarter ended April 1.

Schultz, 64, who announced Monday that he's stepping away from Starbucks as of June 26, sought to bolster his argument by mentioning the credentials of current Disney CEO Bob Iger as similar to his. Iger is another executive mentioned as a possible 2020 presidential candidate.

"President Trump has given license to the fact that someone who is not a politician can potentially run for the presidency," Schultz said. "Whether or not that has anything to do with me remains to be seen."