Prospects faded on Wednesday for quick Obamacare repeal and replacement legislation in the U.S. Congress as a renewed effort by the White House could not end infighting by Republican lawmakers over healthcare policy.

One outside conservative group said progress on a healthcare bill had "stalled" in talks between Republican conservatives and moderates, who had hoped to patch up differences this week.

Heritage Action Chief Executive Mike Needham told reporters his group was even looking at ways to target House moderates known as the Tuesday Group, with attack ads in their districts and other tactics.

Republicans have been railing against President Barack Obama's Affordable Care Act since its enactment in 2010. On Tuesday, some Republican lawmakers expressed hope the Trump White House would unveil a healthcare bill, and some conservatives said a vote by the full House was possible this week.

The legislation has not yet emerged, despite intensive talks with Republican lawmakers led by Vice President Mike Pence. A House Republican leadership aide said on Wednesday that plans remained on track for the divided chamber to begin a more than two-week recess by mid-afternoon on Thursday.

Representative Mark Meadows, chairman of the hard-right House Freedom Caucus, late on Tuesday said, "There’s a concern on my part that if we’re making real progress, that going home sends the wrong message."

Without a breakthrough by week's end, it will be the second time in about two weeks that the White House and House Republicans have fallen short on healthcare.

Still, the negotiations will allow lawmakers to return to their home districts and tell voters they are trying to deliver on a campaign promise that helped them win election.

In an interview with Axios and NBC television, House Majority Leader Kevin McCarthy said Republicans will produce a healthcare bill, but did not provide a timetable.

Late on Tuesday, following a long, closed-door meeting with House Republicans, Pence told reporters there was "good talk, good progress" toward a bill. He did not elaborate.

Republican lawmakers have described the current effort as focusing on maintaining Obamacare's list of essential health benefits, such as mental health coverage and maternity care. But states could apply for waivers if they demonstrated that would improve coverage and reduce costs.

There were discussions of a new provision to create a "backstop" so people with chronic illnesses in high-risk insurance pools do not see their premiums spike if major portions of Obamacare are repealed.

(Reporting By Yasmeen Abutaleb and David Morgan, Writing By Richard Cowan; Editing by David Gregorio)