Bernie Sanders on Sunday came out against a plan being considered by the city of Philadelphia to tax soda as a means of paying for universal pre-kindergarte n programs.

He argued on NBC's "Meet the Press" that it would be regressive, affecting the poorest families who often buy soda precisely because it is inexpensive.

But when host Chuck Todd pressed him about whether the same logic would compel him to oppose a tax on cigarettes, Sanders balked, arguing that cigarettes are a far worse health threat and suggesting that he'd like to see them banned.

"There's a difference between cigarettes and soda," the Vermont senator said. "I am aware of the obesity problem in this country. ... But cigarettes are causing cancer, obviously, and a dozen other diseases. And there is almost the question as to why it remains a legal product in this country."

On the soda tax, Sanders said he would rather see Philadelphia raise money for pre-K programs on the backs of big corporations than the families who buy soda.

"You have large multinational corporations not paying a nickel in federal taxes," he said. "That's where you get the money. Somebody's making $20,000 a year and they buy a bottle of soda, I don't think you charge them 30 cents more for that bottle of soda."

Hillary Clinton, Sanders' rival for the Democratic nomination, said earlier this week that she supports the Philadelphia mayor's proposed soda tax.

"It starts early with working with families, working with kids, building up community resources -- I'm very supportive of the mayor's proposal to tax soda to get universal pre-school for kids," Clinton said. "I mean, we need universal pre-school. And if that's a way to do it, that's how we should do it."