China hasn't "signed and sealed and delivered" a deal yet to drop auto tariffs on cars coming into the country from the United States, despite a tweet on Sunday from President Donald Trump saying China had agreed, but National Economic Council Director Larry Kudlow said Tuesday he and Trump think the tariffs will go away.

"In my view, I think the president expects them to go to zero, and I will say this, the vice premier told a group of us, Bob Lighthizer, Steve Mnuchin, that they were ready to move on a number of items," Kudlow told Fox News "Fox and Friends."

"If they are serious about this, I think they will move very quickly on the car tariffs, and I think they will whack them down to zero. That would be great."

On Sunday, Trump tweeted that "China has agreed to reduce and remove tariffs on cars coming into China from the U.S. Currently the tariff is 40%."

Kudlow, who participated in Trump's meeting with Chinese leader Xi Jinping, noted that there is still a question of commitments that are "very important" that must be reached.

"This is much bigger and much broader than anything we ever talked about," said Kudlow. "It covers a wide variety of areas, including technology, including tariffs, including purchases of various commodities, agricultural and industrial," said Kudlow.

Xi also agreed to a number of "sidebar documents," Kudlow, including putting fentanyl on the list of controlled substances, which could make their sales "eligible for the Chinese death penalty."

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