Congress and the White House reached agreement on a budget deal raising discretionary spending caps for fiscal 2020-21, clearing the way for the Senate Appropriations Committee to begin marking up spending bills. The panel has held back action thus far in anticipation of a bipartisan, bicameral topline agreement, finally reached late last month.

[What the two-year budget deal means for federal spending]

Trump’s push for funding to extend barriers on the southern border, combined with many Democrats’ opposition to it, is likely to produce a clash in the fall. Congress earlier approved $1.3 billion in wall funding for fiscal 2019. Trump asked for an additional $8.6 billion in his fiscal 2020 budget for border barriers — $5 billion in Department of Homeland Security construction accounts, and $3.6 billion for the Pentagon to assist with the project.

Trump earlier this year declared a border emergency and tapped existing statutes to shift $6.7 billion mainly from Pentagon budgets to fund wall construction. The Supreme Court last month cleared the way for the administration to divert $2.5 billion out of defense programs for the wall, blocking a challenge from environmental and other groups.

Shelby’s provision for wall funding is not surprising. At the very least, it sets the table for a negotiation with the Democrat-led House, which did not include any wall funds in its Homeland Security bill, and sought to tie the administration’s hands in transferring military and other funds to the border project.