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Health and Human Services Secretary Tom Price on Monday dismissed the newly released Congressional Budget Office analysis of the House GOP healthcare bill, calling it "just not believable."

Flanked by Office of Management and Budget Director Mick Mulvaney, Price told reporters outside the White House that “we disagree strenuously" with the report and said the CBO considered only a “portion” of the Republican plan.

Price and White House officials are promoting three “phases” of their effort to repeal and replace Obamacare. The House bill represents phase one of the roll out, while other phases include regulatory reform and additional legislation that has yet to be introduced.

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“The fact of the matter is, we’re working on the regulations right now,” Price said.

In "scoring" the House bill, the CBO estimated that 24 million more Americans would be without health insurance by 2026, including 14 million more lacking coverage by 2018.

Price balked at those figures, saying it was "virtually impossible to have that number occur."

“The fact of the matter is (Americans) are going to be able to have a coverage policy that they want for themselves and for their family," he added. "They are going to have the kind of choices that they want. … So we think that CBO simply has it wrong.”

As the officials spoke to reporters, the president tweeted against Obamacare.

If Obamacare is so great, why'd they spend tens of millions of taxpayer dollars to 'hype' it? BAD! #RepealAndReplace https://t.co/5mur5pIFQz — President Trump (@POTUS) March 13, 2017

While Price tried to discredit aspects of the CBO report, Mulvaney pointed to the analysis as evidence that conservative ideals of market competition would bring healthcare premiums down.

“The numbers that I’ve seen in the first glance is that CBO says the premiums will go down by at least 10 percent,” Mulvaney said. The report does estimate an eventual 10 percent decline in premiums, but the short term view shows premiums spiking 15 to 20 percent.

Price would not go so far as to tell lawmakers to explicitly disregard the CBO.

"We will read the report, look into report beyond the top lines and we’ll have further comment tomorrow and talk with our colleagues about why we believe the entire plan that we have recommended moving forward and adopting is one that will provide greater opportunity for folks to purchase coverage they want," Price said.

"I think this was as good a score as we could have hoped for," a GOP aide told NBC.