“That should be long enough of a notice for the replacement process,” he said in a statement on Thursday. “With the Deputy Administrator position also vacant, I’m concerned that a confirmation process could leave the Small Business Administration without a leader well into the fall.”
He added, “The SBA performs an important role for many small businesses and the administration should make small businesses a higher priority by finding a new administrator as quickly as possible.”
SBA press secretary Emily Cain said that the administration was coordinating on the effort.
“The agency is working closely with the White House on transition plans and on the appointment of a successor," she said.
Without a replacement for Mills, the SBA will be the most visible federal agency without a leader.
The announcement from Mills comes days after Democrats and Republicans in the Senate reached a deal to confirm a number of Obama's pending nominees, including heads for the Department of Labor and the Consumer Financial Protection Bureau.
Mills oversaw the SBA as her post was elevated to the Cabinet-level in January, and she has been with the Obama administration since day one.
She will leave office to work at both Harvard University's Kennedy School of Government and Business School, Cain said.
“She also will pursue some business opportunities,” she added.
Mills’s plans to leave at the end of August were first reported by The Washington Post.