Hilda Solis stepping down as labor secretary

Hilda Solis announced that she is stepping down from her post as labor secretary, CBS News has confirmed. She sent a letter to President Obama today notifying him of her retirement.

Solis was nominated to the position the same day the president was inaugurated in 2009, serving through the president's entire first term. She ran the Labor Department during the worst economic recession since the Great Depression. The department, which calculates unemployment statistics, came under criticism during the presidential campaign for a steep drop in the jobless numbers from above 8 percent to below 8 percent right before Election Day.

President Obama called her "a critical member" of his economic team who has helped put "millions" of people back to work. "Hilda Solis has been a tireless champion for working families," the president wrote in a statement.

Before her current position, she was a member of Congress, representing California since 2001 but left that job to be the first Hispanic woman to run the agency.

The president must now name a replacement that must go through the Senate confirmation process. CBS News learned today that the president intends to nominate his chief of staff, Jack Lew, to run the Treasury Department.

Solis joins Secretary of State Hillary Clinton, Treasury Secretary Timothy Geithner, CIA Director David Petraeus and Defense Secretary Leon Panetta in stepping down from their cabinet-level posts.

A White House official says Health and Human Services Secretary Kathleen Sebelius, Veterans Affairs Secretary Eric Shinseki and Attorney General Eric Holder plan to remain in their positions.