House Republicans are preparing to take action on a $15 billion rescissions package in coming weeks amid a conservative push for Congress to claw back spending as lawmakers return from recess.

The White House is considering tweaking its initial proposal - an idea spearheaded by House Majority Leader Kevin McCarthy (R-Calif.) after discussions with President Trump in April - as GOP leadership is still short of the votes needed to pass the measure.

While the package still faces some pushback - with critics fearing it could hinder future bipartisan negotiations - House GOP leadership is currently whipping the measure as pressure mounts on the party's lawmakers to slash spending ahead of the midterm election cycle.

"Support for the President's rescissions request is growing by the day and Leader McCarthy continues to actively support the whip operation to send these spending cuts to the Senate," McCarthy spokesman Matt Sparks told The Hill in a statement. "The House is expected to consider it when we return from the district work period."

Conservative activist groups including FreedomWorks, the Heritage Foundation and Tea Party Patriots have recently expressed their support of the idea, pushing Republicans to act on the rollback in funding following Congress's $1.3 trillion omnibus spending bill.

"Small steps are better than no steps. Oftentimes, these unobligated funds are used as fake offsets in appropriations bills to allow for higher spending," FreedomWorks president Adam Brandon wrote of the package. "Therefore, although not intended to be spent for their original purpose, it is important to take away the opportunity to repurpose the spending as offsets by rescinding them."

While the rescissions would cut just a fraction of the spending in the massive government funding bill, proponents argue it's a good start to a more fiscally conservative approach to governing.

"Approving this initial $15.4 billion rescissions request in full -- pulling back funds sitting in useless accounts that can only otherwise be used to spend more in the future -- is a task that conservatives in Congress should wholeheartedly endorse," Brandon continued. "It is one of few opportunities to exercise any semblance of fiscal discipline. It is only one small step towards actually tackling Washington's out-of-control spending addiction, but it represents a chance to begin this fight."

Democrats have voiced strong opposition to the White House proposal, with House Minority Whip Steny Hoyer (D-Md.) blasting its call to cut a contingency fund for the Children's Health Insurance Program (CHIP) while leaving defense discretionary spending intact.

McCarthy dismissed allegations it would negatively impact CHIP, arguing it targets untouchable funding and saves taxpayers money.

GOP Sens. Mike Lee (Utah), Ron Johnson (Wis.), Pat Toomey (Pa.), Joni Ernst (Iowa), David Perdue (Ga.), John Kennedy (La.), Rand Paul (Ky.), Jeff Flake (Ariz.) and Ben Sasse (Neb.) introduced the rescissions package in the upper chamber late last week, with supporters hoping it would be taken up in committee before the window for it to be discharged runs out.

"Yes, a $15 billion spending reduction is a drop in the bucket compared to a $15 trillion debt," Lee said in a statement. "But we have to start cutting spending somewhere."