A spokesman for the Mexican Embassy did not immediately respond Wednesday to a request for comment.
The plan, which has been debated internally for months, is part of a broader push by the Trump administration to redirect billions in foreign assistance to other priorities.
The administration has yet to spend nearly $3 billion in foreign aid, money allocated last year by Congress with broad bipartisan support.
Hundreds of millions of dollars meant to help stabilize Syria and support Palestinian schools and hospitals has already been redirected.
But it has long been frustrated that Congress provides billions for foreign aid while refusing to fund its immigration priorities.
The money will be transferred from the State Department to the Department of Homeland Security, and then sent to Mexico.
That led to the widely criticized practice of separating children from their parents at the border, which spurred a humanitarian and political crisis for Mr. Trump. »