Republican Sens. Lindsey Graham, Rob Portman, and Susan Collins, plus Democratic Sens. Joe Manchin and Chris Coons are reportedly working on the letter. While the full list of signees is not finalized, Manchin told Politico they’re aiming for the support of 20 Democrats and 20 Republicans.

A leaked draft of the letter does not directly mention the more than $5 billion Trump has adamantly demanded a border wall but notes the administration’s request for “addressing the humanitarian and security challenges at our nation’s southern border.”

“We believe that such requests deserve consideration, through regular order, a process we support,” the draft letter continues.

In exchange for a three-week reopening of the government, the senators promise to commit that time to make “our best efforts following regular order in the appropriate committees and mark up bipartisan legislation relating to your request. This would include debating and voting on investments on the Southern border that are necessary, effective, and appropriate to accomplish that goal.”

The effectiveness of such a letter is in question. A Trump administration official told Axios “Sen. Graham et al. were told last week that a short term reopen for the Senate to work on a solution was DOA [dead on arrival],” adding that the White House said they “didn’t need to reopen government for the legislative branch—which is fully funded—to work.”