Donald Trump‘s decision to weigh in on a border deal being negotiated in the Senate is imperiling its passage even before the details of that agreement have been announced.

The former president took a hard line Wednesday on the possible agreement, demanded by Republicans in exchange for further aid to Ukraine. His comments, posted on Truth Social, reflect the views of House conservatives, who take an “all-or-nothing” approach to border security, but his sway over the party only serves to complicate its path through the lower chamber.