Joe Biden slammed Sen. Elizabeth Warren (D-MA) at the Democrat presidential debate on Thursday for not being honest about the cost of Medicare for All.

“This is about candor, honesty,” the former vice president said, before proceeding to say that Warren’s proposal for funding Medicare for All was improbable. “The tax of two percent that [Warren] is talking about, that raises about $3 billion. Guess what? That leaves you $28 billion short.”

Biden added that Warren’s proposal would not be deductible free, but instead the costs would end up being passed on to taxpayers in another form.

“There will be a deductible in your paycheck,” he said. “The middle class person, someone making 60 grand with three kids, they’re going to end up paying $5,000 more.”

Since announcing his presidential campaign in late April, Biden has lambasted Medicare for All as overly ambitious and difficult to implement. During a CNN interview in July, Biden claimed that Sanders was the only candidate, out of a majority of those running that have endorsed Medicare for All, to be upfront about the costs and consequences of the policy.

“Bernie’s been very honest about it. He said you’re going to have to raise taxes on the middle class. He said it’s going to end all private insurance. I mean, he’s been straightforward about it. And he’s making his case,” Biden said, before adding other Democrats have not been as transparent.