By MJ Lee, Deirdre Walsh, Lauren Fox and Phil Mattingly

WASHINGTON (CNN) -- The House will not vote on the Republican health care bill Thursday, a GOP aide said, further putting efforts to repeal and replace Obamacare in jeopardy.

The decision came after multiple high-level and tense meetings at the White House and Capitol that failed to broker a compromise.

House Speaker Paul Ryan abruptly postponed, for a second time, a scheduled press briefing, instead staying behind closed doors to negotiate. 

The conservative House Freedom Caucus, whose members appear to hold the key to any agreement on a final bill, met with President Donald Trump earlier Thursday. The session started with a standing ovation for the President, but there was little obvious progress they could point to, a GOP source said.

One senior administration official described the meeting with one word: "Intense."

The Freedom Caucus has been delivered a "final offer," said a member of House leadership, chief deputy whip Patrick McHenry. "It's really in the hands of the members there to accept or reject the White House's offer."

"This is the final offer," McHenry said. "We have a package, they have an offer, and? they can accept or reject it." 

Freedom Caucus Chairman Mark Meadows said there's no deal yet.

"There are not enough votes as of 1:30 p.m. today," he told reporters.

Moderates heading to White House

The moderate "Tuesday Group" had seven boxes of pizza, as well as Doritos and Baked Lays, delivered to a room in the Capitol. And dozens of Republicans are circulating from meeting to meeting, including one-on-one sessions with Ryan.

Moderate Republicans, including members of the Tuesday Group, were meeting Thursday afternoon with Ryan and will travel to the White House later in the day.

Tuesday Group leader Charlie Dent of Pennsylvania said he's still a no on the bill. Asked if there will be a vote Thursday night, he replied: "I have no idea."

The White House remains upbeat, press secretary Sean Spicer said. 

"Through an open and deliberative process, the President and his team have helped to negotiate a very, very strong bill," Spicer told reporters. "He was on the phone last night well into the 11 o'clock hour with members on an individual basis discussing their support for the bill."

Anger at the Freedom Caucus

But thus far, there's no deal -- and frustration is mounting.

"This bill is collapsing," one House Republican, who declined to speak on the record, told CNN.

The challenge for leaders as they count their votes is daunting: Give conservatives too much of what they want and risk losing the moderates, but keep the moderates on board and conservatives could walk. 

Leadership is keenly aware that every vote counts: Republicans can't lose more than 21 of their caucus and still pass the bill, since no Democrats are expected to support it. According to CNN's ongoing whip count, 25 House Republicans have said they will vote against the bill, and four more have indicated they are likely to oppose it, though negotiations were ongoing Thursday. 

Trump is now seeing and feeling firsthand what it is like to work with the Freedom Caucus, a top GOP source said, that they are incredibly frustrating because they don't really want to get to yes -- and keep moving the goalposts.

Alabama GOP Rep. Bradley Byrne, emerging from a meeting with top House leaders, blasted the House GOP leadership's move to continue talks with the hard right in the Freedom Caucus while leaving the bulk of other members in the dark.

"I think the window for making decisions is rapidly closing. We need a vote or go home," said Byrne, a member of a large group of fiscal conservatives, the Republican Study Committee.

A senior GOP aide said the Freedom Caucus simply won't close the deal.

"They don't know how to get to yes. They just don't. And it's putting the whole process at risk right now," the aide said.

Meadows maintains he wants an agreement.

"We have discussed some options and we're trying to get creative and make sure that those options are something that's acceptable to the administration, because its ultimately the President that's going to decide yes or no on what happens here," he said at the White House.

Change is scaring away moderates

A key element of the negotiations between the Freedom Caucus and the White House revolves around the so-called "essential health benefits." The White House is working to possibly include the repeal of Obamacare requirements that certain benefits -- like mental health coverage, drug addiction coverage and maternity care -- be required in insurance plans. 

But those changes have moderates saying they can't back the bill.

"It has always been the case -- pull the bill one way, risk losing members on the other end," a lawmaker involved told CNN.

Ryan huddled Wednesday night in his office with his top deputies and GOP moderates. But after several hours, no members came to talk to the reporters waiting outside the meetings. Most members used back exits to leave and the big sticking points remained unresolved. 

A member who was in the late-night Ryan meeting said tensions were running high.

"A lot of people don't realize what the implications of that are," the member said of stripping out essential health benefits. "So we're gonna railroad this thing through and there's going to be even more people pissed off -- our constituents, stakeholders."

Many GOP members are frustrated with how leadership has handled the negotiations in the past 24 hours.

"I think the chances for getting a bill done this week gets smaller -- doesn't go to zero, no such thing as never or impossible -- but I think the chances of passing this bill get a ... lot lower if we don't do it this week," one member said.

"The vast majority of us in the Republican conference have been left out of these discussions and we have no idea what's going on, and I think that is a problem for our leadership and I think it's a growing problem for the chances of this bill," said Byrne, who is a supporter of the health care bill and part of the whip operation to help pass it. 

Byrne complained that the Freedom Caucus continues to throw out an expanding list of demands and suggested there was little to be done to get some in that group on board and it was time to move on. 

"Those members don't change, so at some point, you've got to say there's nothing in the world that's going to change their minds," Byrne said.

What's in the bill

The bill introduced earlier this month would roll back many of the Obamacare taxes and eradicate the individual mandate. Instead of the subsidies available under Obamacare, officially known as the Affordable Care Act, the GOP plan provides Americans with refundable tax credits to purchase health insurance.

The bill also significantly restructures Medicaid and allows states to require able-bodied adults to work if they want to be eligible for the program. After 2020, states will no longer be able to expand Medicaid like they could under Obamacare and states that haven't expanded the program at all are barred from doing so.

However, the GOP bill still includes some of the most popular pieces of Obamacare, including letting children stay on their parents' insurance plans until the age of 26 and including protections for people with pre-existing conditions, though insurers would be allowed to charge higher premiums to individuals whose coverage has lapsed. 

The non-partisan Congressional Budget Office estimated that 24 million fewer Americans would be covered under this bill than under Obamacare by 2026 if the bill is becomes law in its current form.

This story will continue to be updated as developments warrant.
   
 CNN's Dana Bash, Jeff Zeleny, Tal Kopan and Stephen Collinson contributed to this report. 
   
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