Story highlights The Congressional Budget Office released its report Monday

The report found millions would not have health care coverage under the GOP plan

Washington (CNN) Sen. Bill Cassidy blasted the White House Tuesday after a Congressional Budget Office report showed that 24 million people could lose their health insurance by 2026 under the Republican plan to replace Obamacare.

"That's not what President Trump promised," Cassidy, Republican of Louisiana, told CNN. "That's not what Republicans ran on."

Cassidy said he is deeply concerned about the coverage loss under the bill, as depicted by Monday's release of the CBO score, and wants changes to it. He also criticized the White House for trying to discredit the CBO.

Bill Cassidy, republican candidate in 2014 for U.S. Senator from Louisiana, speaks during the final day of the 2014 Republican Leadership Conference on May 31, 2014 in New Orleans, Louisiana.

"You have to have an umpire, even if the umpire occasionally gets it wrong, because otherwise you are only accepting analysis by people with motivations define certain answers, and so I am very reluctant to disregard what the CBO score is," Cassidy said.

Just days before he was inaugurated, Trump said the Republican health care plan would include " insurance for everybody ." At the time, the comment sent Republican leaders in the Capitol scrambling to explain that Trump really meant the plan would include "insurance access for everybody" -- a big difference.

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