The issue focused on the non-deployed members of the Trump campaign, as they have not been required to file for an election-year return.

Sens. Ben Sasse, R-Neb., and Mike Lee, R-Utah, have also called on the president to release his tax returns, with Sasse saying in a statement on Friday: "The American people deserve to know if he is being paid to do this."

The president's tax returns are a campaign issue,