House Republicans are under pressure from the White House to pass a new version of legislation to repeal and replace Obamacare, but GOP lawmakers are treading carefully after two previous failed attempts, and have not committed to holding a vote yet.

An amended version of the bill was released Thursday that tries to bridge the gap between centrist Republicans and the more conservative members of the House Freedom Caucus.

Sources said the White House is pushing for a vote on the bill next week, just days after President Trump stressed that a repeal bill is still needed so Republicans can move on to tax reform and other issues.

But a senior House Republican aide told the Washington Examiner that lawmakers will spend several days examining the text, and carefully weighing whether the votes are there among Republicans to pass it.

"The agreement that matters is the one that gets us to 216," the aide said. "We're not going to set arbitrary deadlines."

The aide added that there is no legislative text yet, and therefore, "no agreement to do a whip count on." The House Rules Committee also has no plans to prepare for a vote because there is no formal language yet, according to another staffer.

Republicans will hold a Saturday phone call to go over the amended healthcare bill, to start getting a sense of where the support lies. But the aide said that call is not expected to be used to decide whether to go ahead with a vote, and that further review of the plan by lawmakers will likely be needed.

Despite this cautious approach, Rep. Tom MacArthur, R-N.J., was already holding out the idea that a vote would happen next week.

"It's not dead," MacArthur told NJ.com on Tuesday. "I spoke with the vice president and the speaker over the weekend, and it's moving."

"They have to get it into a form that the Senate can actually act on it. That's what they're in the final stages of doing," MacArthur said. "If we think we have enough votes, we'll go forward next week."

That plan would place an added time crunch on Republicans if they hope to pass the bill next week, when they are also facing a deadline to extend funding for the federal government.

Funding will expire at the end of April 28, which means lawmakers will have to fund the government for the rest of the fiscal year, or agree to a short-term extension.

A second GOP aide told the Examiner that some lawmakers are expecting some kind of short-term extension. But the first aide said a short-term extension would not necessarily be sought in order to carve out time to pass a healthcare bill, and that the idea is being talked about primarily because extra time is often needed to pass these bills.

It's not clear, for example, if the House Freedom Caucus would balk at a longer-term spending bill, but if they did, that could prompt Republicans to seek more time to sort out those differences.

Republicans are pressuring themselves to quickly sort out bills related to spending and healthcare, so they can move on to tax reform.

In recent days, top Republicans have opened the door to a longer timetable to complete tax reform.

After Treasury Secretary Steve Mnuchin remarked that it was "not realistic" to complete necessary reforms by August, Speaker Paul Ryan and House Ways and Means Chairman Kevin Brady both said that while completing reforms by August is ideal, they want it done by the end of the year.

"This will be done in 2017, that is our timeline, we would like to get it done as soon as possible," Ryan said during a visit to London this week.

"As soon as possible for us is by the end of summer but we're going to take our time to get it right," Ryan said. "We can clearly get this done by the end of summer but if it needs to go a little longer, we'll do that."

Robert King contributed to this story.