President Trump has begun pushing aggressively for Republicans to take another bite at passing health-care reform, even soliciting allies in Congress to help him with the task.

But so far, senior GOP lawmakers on the Hill are balking at the push, with aides and lawmakers saying they would either wait on the White House to introduce its own health-care bill or stick to narrower, possibly bipartisan priorities like lowering drug costs.

“We’ve discussed Obamacare thoroughly over the last 10 years, and we know each other’s differing opinions, and so we’re focusing on reducing health-care costs,” said Sen. Lamar Alexander (R-TN), who chairs the Senate Committee on Health, Education, Labor & Pensions, through which any major Obamacare replacement plan must go. “I’m looking forward to hearing what the president’s plan is,” he added.

The disinterest threatens to pit Republican lawmakers against the head of their party. And it could end up complicating the GOP’s agenda in the coming weeks, forcing them back into the electorally tricky terrain of health-care politics.

They may not have a choice. Feeling vindicated after Special Counsel Robert Mueller’s report found his 2016 campaign did not collude with Russia, an energized Trump went to Capitol Hill on Tuesday and urged Republican senators to renew efforts to repeal and replace President Obama’s signature health care law. A day earlier, Trump’s Department of Justice—reportedly egged on by West Wing officials—sided with a legal challenge to Obamacare that would strike down the entire law.

Republican lawmakers reacted publicly with surprise; privately, many in the GOP’s political class were horrified that Trump would move to restart a health-care campaign that fell short when the GOP controlled all of Congress—and backfired by propelling Democrats into the House majority in the 2018 midterm.

“Just when you think they know what they’re doing,” one top GOP operative, who worked on the 2018 campaigns, said sarcastically of his party’s abrupt turn back into the health care debates.

But, since then, the White House has showed no signs of backing off. On Wednesday, Vice President Mike Pence’s top aide, Marc Short, said the administration would be putting together a health-care proposal. On Thursday, the president tweeted that progress was being made “legislatively.” Later, Trump revealed that he had tasked three senators—John Barrasso (R-WY), Bill Cassidy (R-LA), and Rick Scott (R-FL)—to come up with a plan.

Scott, said a spokesman, “has talked to the president at length about the senator’s commitment to improving the quality of health care and lowering costs—particularly the rising costs of prescription drugs. He’s been talking with colleagues about new ideas to address rising health care costs that we can get passed this year.” Barrasso’s office declined to comment; Cassidy’s office did not respond to a request for comment.

Trump told reporters that while the lawmakers were “working on a plan now,” they and his administration were in “no very great rush,” choosing to let the legal challenges play out first.

Elsewhere on the Hill, there was outright inertia over getting a health care bill crafted. One senior Senate Republican aide told The Daily Beast that the sentiment among lawmakers was to wait for the White House “to send something up” before they made any pronouncements—a sentiment echoed by lawmakers themselves.

“We’re waiting on the president’s plan,” said Sen. Pat Roberts (R-KS). “He made a lot of remarks yesterday, but one of them is he thought that should be a Republican initiative, so I’ll be very interested in what plan the administration would like to see go forward.”

Sen. Lindsey Graham (R-SC), a key ally of the president, co-authored the GOP’s unsuccessful last-ditch repeal-and-replace bill alongside Cassidy. But he too seemed to dismiss the most recent push as a fool’s errand.

“We had the whole conversation last time about repeal-and-replace,” Graham told reporters. “My belief is that we need a new approach,” he added, saying any health-care reforms should be “state-centric.”

Whether the reluctance of Hill Republicans to re-engage in the health care debate is sustainable may be tested in the coming weeks. On Thursday, the Club for Growth, one of the top conservative advocacy groups in D.C., called on Senate lawmakers to work with the president to “craft a beautiful health-care alternative” to Obamacare. Scott Parkinson, the group’s vice president of government affairs, told The Daily Beast that it would be insufficient for those senators merely to wait for the administration to put together its own plan.

“ It’s clear President Trump will have to lead because the congressional Republicans are shell-shocked and don’t know what to do. ” — Scott Parkinson, vice president of government affairs, Club for Growth

“I think you can see the administration putting out a guiding document. But legislation is crafted in Congress,” said Parkinson. “It’s clear President Trump will have to lead because the congressional Republicans are shell-shocked and don’t know what to do.”

For now, at least, Republicans appear far more eager to avoid talk of Obamacare replacements in favor of focusing on Democrats’ plans to implement single-payer health care. Having failed in their past attempts to put together a bill that would maintain some of Obamacare’s more popular provisions (including the prohibition of discriminating against people with pre-existing conditions), while undertaking conservative reforms elsewhere (including ending the Medicaid expansion and eliminating some of the law’s tax credits), few could imagine how they’d find a winning legislative formula this go around, especially with the House of Representatives now in Democratic hands. Instead, they suggested that Trump show them the way first.

“His announcement yesterday came as a little bit of a surprise,” said Sen. John Cornyn (R-TX), the No. 2 Republican in the Senate, “so we’re anxious to see what the administration proposes.”