Sens. Mike Lee and Jerry Moran jointly announced Monday night that they will oppose a vote to open debate on the Senate GOP's healthcare bill, meaning Republicans currently do not have the votes to advance the legislation in its current form.

Lee, R-Utah, and Moran, R-Kan., announced their opposition to the bill in tweets in which they cited one another, but they issued separate statements.

With Sens. Rand Paul, R-Ky., and Susan Collins, R-Maine, already coming out against advancing the healthcare bill, Senate Majority Leader Mitch McConnell, R-Ky., no longer has the votes he needs to have least 50 of 52 Republicans on board.

"After conferring with trusted experts regarding the latest version of the Consumer Freedom Amendment, I have decided I cannot support the current version of the Better Care Reconciliation Act," Lee said. "In addition to not repealing all of the Obamacare taxes, it doesn't go far enough in lowering premiums for middle class families; nor does it create enough free space from the most costly Obamacare regulations."

Lee is referring to a tweaked proposal by his ally and colleague Sen. Ted Cruz, R-Texas. The amendment allows insurers to offer less-expensive plans that don't have to comply with most of Obamacare's wide range of regulations as long as they also offer a plan that is fully compliant.

Moran, a more centrist senator, cited the "closed-door" process by which the bill was written for not supporting proceeding on the debate of it.

"There are serious problems with Obamacare, and my goal remains what it has been for a long time: to repeal and replace it," Moran said. "This closed-door process has yielded the BCRA, which fails to repeal the Affordable Care Act or address healthcare's rising costs. For the same reasons I could not support the previous version of this bill, I cannot support this one."

Moran added "we should not put our stamp of approval on bad policy."

Moran called for the Senate to "start fresh with an open legislative process to develop innovative solutions that provide greater personal choice, protections for pre-existing conditions, increased access and lower overall costs for Kansans."

Some House conservatives were also wanting to start anew with a bill that repeals more of Obamacare. Rep. Mark Meadows, R-N.C., head of the conservative House Freedom Caucus, tweeted that Congress needs a reset.

"Time for full repeal of #Obamacare let's put the same thing on President Trump's desk that we put on President Obama's desk," he tweeted.

The House passed its version of partial Obamacare repeal back in May by a razor-thin margin of 217-213.

While conservatives were upset that the bill didn't do enough to repeal Obamacare, centrists were wary of signing on to the bill's major cuts to Medicaid.

McConnell announced Saturday that the vote on the healthcare bill would be delayed after Sen. John McCain, R-Ariz., said he would be spending a week in Arizona to recover from a procedure in which a blood clot was removed above his left eye.

Republicans expected to vote on the bill this week, but were waiting for a score from the Congressional Budget Office, which will project how much the legislation would cost and how many people could become uninsured if it were to become law.

The unexpected news comes as a group of senators and GOP Senate leadership are scheduled to meet at the White House with President Trump on a strategy session for getting the healthcare bill approved.

"This second failure of Trumpcare is proof positive that the core of this bill is unworkable," Senate Minority Leader Chuck Schumer, D-N.Y., said in a statement Monday night. "Rather than repeating the same failed, partisan process yet again, Republicans should start from scratch and work with Democrats on a bill that lowers premiums, provides long term stability to the markets and improves our health care system."

Robert King contributed to this story.