Republican leaders may make more revisions to their plan to repeal parts of Obamacare to encourage more centrists to support the legislation, after a day in which many signaled they can't support the bill in its latest form.

House Speaker Paul Ryan, R-Wis., House Majority Leader Kevin McCarthy, R-Calif., and Health and Human Services Secretary Tom Price met Thursday with GOP lawmakers opposed to the bill. Republicans still don't have the 217 votes they need to pass the American Health Care Act, and a vote this week appears increasingly doubtful.

Reports late Thursday indicated that Republicans had formally decided not to push a vote Friday, and the GOP hadn't teed up any Friday votes during the day. That decision will likely prevent the House from delivering a vote for President Trump by Saturday, his 100th day in office — a milestone Trump had hoped to mark with a vote to repeal the law.

But while House leaders have pledged they won't bring the bill to the floor if they don't have the votes, they aren't ruling out a weekend vote as they have told members to stay "flexible," some lawmakers said.

Rep. Chris Collins, R-N.Y., suggested additional concessions may be made to persuade more centrists to support the legislation.

"I think we understand that the MacArthur language is the language," he said about the amendment made public this week that would allow states to opt out of certain Obamacare requirements. "But there are a couple of other tweaks that could occur on the Medicaid side to help in some extent, without it being such a huge issue that it would lose anybody."

Centrists opposed to the current version have noted that the bill would cut $880 billion from Medicaid, saying they are concerned about taking coverage away from low-income constituents. Collins said they are worried about provisions in the legislation that would allow states to change their Medicaid funding to a block grant or to a system that would place a per-capita cap on funding, structures that would limit spending but also give states more flexibility about how to use federal dollars.

The amendment, authored by Rep. Tom MacArthur, R-N.J., was able to bring a large majority of the conservative House Freedom Caucus on board, which has about three dozen members, putting pressure on centrist holdouts to add their support.

The centrist Tuesday Group has about 50 members, but the group itself doesn't vote as a bloc like the Freedom Caucus does. The caucus needs at least 80 percent of its members to support legislation before it will formally back it.

GOP leadership is now targeting members in the Tuesday Group to get on board.

Fear is a powerful motivator among centrists worried about losing their seats because of the tough vote, Collins noted. He said he told several centrist colleagues that "in a in a year and a half you will see commercials on TV attacking you on something."

Collins added that he told skeptical New York centrists that the changes won't affect them as the liberal state won't seek to use the MacArthur provision, which allows for waivers to get out of Obamacare's insurance regulations.

"I am just trying to soothe the waters to remind people afraid of their next election they are gonna get attacked anyways, even if their opponent makes it up," he said.

But some undecided lawmakers are skeptical of the policy behind the amendment.

Rep. Mario Diaz-Balart, R-Fla., said the legislation raised some "red flags" for him, especially about whether people with pre-existing conditions would be protected.

Diaz-Balart last month said he would vote for the bill but is now undecided.

Another member, Rep. Rob Wittman, R-Va., was a no on the bill last month but is now undecided.

Wittman said he needs more time to review the changes and talk with constituents about the impact. He told House leadership that he would need more time to look at it, a sentiment that other lawmakers have echoed.

Centrists who said they would vote "no" on the bill say they haven't been contacted by leadership about potential sweeteners, including Reps. Charlie Dent, R-Pa., and Dan Donovan, R-N.Y.

The Hill's "Whip List" shows that 19 Republicans are planning to vote "no" on the revised legislation.

Collins said a floor vote wouldn't happen until after Congress passes a spending bill. Of travel plans for the weekend, he said, "It's been suggested that we stay flexible."

"Since I'm going to the White House Correspondent's Dinner Saturday night I'm going to be here anyway," he said.