Some top Republicans are saying there won’t be a deal on the Deferred Action for Childhood Arrivals program — the Obama-era immigration order that President Donald Trump plans to sunset in March — until after tax reform.

And one key conservative House member explicitly laid out why: Trump’s voters won’t like it if the first piece of substantial legislation passed by a Republican-controlled Congress and White House is about undocumented immigrants.

“I think if the very first thing we do substantially on legislation is DACA, that makes it extremely difficult for the Trump voter,” Rep. Mark Meadows (R-NC), who chairs the House’s conservative Freedom Caucus, told reporters Tuesday. “Just that’s a political reality.”

Meadows continued:

I’m not trying to minimize the other things that have been signed into law, but I mean in terms of four or five issues that were campaign issues, immigration was one of them — if the very first thing we do is to deal with DACA, it would have negative ramifications for many conservatives.

In other words, there is a priority list, and massive tax cuts, which are shaping up to be a bonanza for the already wealthy, outrank addressing the 800,000 undocumented young adults, many of whom are currently working and going to school, who were protected from deportation under former President Barack Obama’s DACA order.

On Tuesday, House Majority Leader Rep. Kevin McCarthy (R-CA) said Trump is behind this calendar decision, despite tweeting last month that a deal on DACA was coming soon. Senate Republicans said there have been no concrete decisions on a timeline for DACA.

“The first thing he said is he wants to do tax reform first,” McCarthy said of a meeting with Trump. “He doesn’t want to mix them together.”

Meadows’s admission on why this is the case is striking, but not surprising. Trump largely rallied support on an anti-immigration message and campaigned on a “tough on enforcement,” “tough on borders” platform. While a DACA deal would allow Congress to do something on immigration, and would almost certainly include some kind of border security provision, it’s far from a clear-cut conservative win on immigration policy.

Almost every legislative option to enshrine DACA into law — even those sponsored by Republicans — have proposed giving undocumented immigrants an eventual path to citizenship, which some ultraconservatives have decried as “amnesty.”

After several failed attempts to repeal Obamacare, the pressure is on congressional Republicans to deliver Trump’s base a legislative win. And Meadows doesn’t think a deal on DACA — which would have to be bipartisan because of the Senate’s 60-vote threshold — would deliver.