On Monday night, 2020 candidate Joe Biden wouldn’t say whether he’d veto Medicare for All, which aims to provide free health care to every American, if he were elected president.

During a pre-taped interview, MSNBC host Lawrence O’Donnell presented Biden with a hypothetical in which 2020 rival Sen. Bernie Sanders (I-VT) manages to pass his proposed Medicare for All bill in the Senate while House Speaker Nancy Pelosi (D-CA) passes a similar one in the House after Biden wins the presidency.

“It comes to your desk. Do you veto it?” O’Donnell asked.

“I would veto anything that delays providing the security and the certainty of health care being available now,” the former vice president responded. “If they got that through by some miracle and there was an epiphany that occurred and some miracle occurred that said okay, it’s passed, then you gotta look at the cost.”

He asserted that the estimated $32 trillion price tag (which he erroneously stated as being $35 trillion) on Medicare for All over ten years would be a problem.

“Look, my opposition isn’t to the principle that you should have Medicare. Everybody…health care should be a right in America,” Biden told O’Donnell. “My opposition relates to whether or not A, it’s doable, two, what the cost is and the consequences for the rest of the budget are.”

“How are you going to find $35 trillion dollars over the next ten years without having profound impacts on everything from taxes for middle class and working class people as well as the impact on the rest of the budget?” he asked.

Per Vox, economists at the libertarian-leaning think tank Mercatus Center have found that while federal spending would increase substantially under Medicare for All, overall spending on health care would actually go down slightly even as coverage expands.

Biden has argued against Sanders’ signature universal health care proposal on the grounds that it would “get rid” of the Affordable Care Act. The former vice president’s campaign proposal on health care seeks to build on Obamacare instead.

Watch Biden below: