Trump’s delay on a tax proposal is hurting Ryan’s ability to get support for his plan among his party members. Representative Mark Meadows, who chairs the House Freedom Caucus, said his bloc of three-dozen ultraconservatives is waiting to hear from Trump on a tax plan before endorsing anything. Meadows’s group most recently scuttled Trump and Ryan’s efforts to shepherd an Obamacare replacement bill through the House, arguing that it didn’t hew to conservative principles.

“I think a lot of people are waiting to see which way the president wants to go,” the North Carolina Republican said in an interview Tuesday. “I think on the border-adjustment tax issue, they’re just waiting to see which way he wants to go and how compelling of a case he wants to make on that.”

If Trump decides to impose tariffs -- he has called for tariffs of as much as 35 percent on products made by companies that move their production from the U.S. to other countries -- instead of backing the border-adjusted tax, he could encounter resistance from the House conservatives.

“I’m typically not a tariff fan” because they generally lead to retaliatory tariffs and end up slowing growth, Meadows said.

Bipartisan Efforts

The White House is also said to be in the early stages of gauging Democratic support for a tax overhaul in case it can’t get House Republicans on board. Cohn met on March 21 with Representative Richard Neal, the top Democrat on the Ways and Means panel, to discuss tax measures, according to a person familiar with the meeting who asked not to be named because the details are private. Cohn indicated that the White House wants to write a tax plan that Democrats can support, but didn’t offer specifics other than to suggest that Trump wants no absolute tax cut for upper earners, as Mnuchin has indicated, the person said.

If the White House does pursue a tax plan with bipartisan support, it would mean a radically different approach than the Ryan-backed blueprint, which includes tax cuts for the highest earners -- a non-starter for Democrats.

By crafting their tax blueprint last year, “House Republicans came to consensus on tax policy issues, which gives them a head start on everybody else,” said Michael Steel, a managing director at lobbying firm Hamilton Place Strategies and a former spokesman for Republicans on the Ways and Means committee.

But even with that head start, Ryan reiterated the difficulty of coordinating a tax overhaul during an event in Washington on Wednesday.

“The House has a plan, but the Senate doesn’t quite have one yet,” he said. “They’re working on one. The White House hasn’t nailed it down, so even the three entities aren’t on the same page yet on tax reform.”