Economist Larry Summers said Monday that roughly 10,000 more Americans will die each year if Republican tax-reform legislation passes and includes a repeal of the ObamaCare individual mandate.

"I think this bill is very dangerous," Summers said on CNBC's "Squawk Box."

"When people lose health insurance, they're less likely to get preventive care, they're more likely to defer health care they need, and ultimately they're more likely to die."

The Senate passed its tax-reform legislation early Saturday morning. The upper chamber's bill includes a repeal of the individual mandate, while the House's tax-reform bill does not.

ADVERTISEMENT

Summers's estimate is based on a Congressional Budget Office report that 13 million Americans would opt out of ObamaCare if the individual mandate is repealed.

Summers, who served as former President Clinton's Treasury secretary and former President Obama's National Economic Council director, said it's hard to quantify the number of deaths precisely, but called an estimate that thousands will die because of the bill "very conservative."

Summers also said that health care needs improvements in terms of accessibility and cost, adding that he’s not optimistic there will be a bipartisan solution in the near future.

"I think it would be great to start doing things in a bipartisan way, but that's going to require not passing major pieces of legislation hours after the relevant staffs have had a chance to evaluate them," he said.

"That’s going to require holding hearings on pieces of major legislation, that’s going to require doing all sorts of things that it doesn’t look like the administration and the current congressional leadership want to do," he continued.