(Jacquelyn Martin/AP)

Miriam Sapiro is expected to be named this week as acting United States Trade Representative, taking over for acting trade rep Demetrios Marantis when he leaves on Wednesday to take a top job at Square, the mobile payments company.

Sapiro has been deputy United States Trade Representative since January 2010, handling trade policies in the Americas, Europe and the Middle East.

Sapiro will be in the new job pending Senate confirmation of deputy National Security Adviser for International Economic Affairs Mike Froman, who was nominated May 2 to be U.S. Trade Rep.