WASHINGTON (AP) — House Democrats have filed a lawsuit aimed at preventing President Donald Trump from spending more money than Congress has approved to erect barriers along the southwestern border.

Democrats say Trump’s attempt to transfer billions of dollars from several programs to wall construction violates the Constitution, which gives Congress control over spending. The 45-page complaint was filed Friday in the U.S. District Court for the District of Columbia.

House Speaker Nancy Pelosi calls Trump’s act a “brazen assault” on the Constitution.

Congress approved just under $1.4 billion for work on border barricades. Trump has asserted he can use his powers as chief executive to transfer another $6.7 billion to wall construction.

Attorneys general from 20 states, plus environmental and progressive groups, have filed other lawsuits aimed at blocking the transfers.