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Secretary of Labor Hilda Solis has stepped down.

The first Latina to lead a federal agency, Solis joined the Obama administration back in 2009 after representing California in the House of Representatives. She said in a letter to colleagues that she was leaving her post to "begin a new future" by returning to her roots. She calls her departure "one of the most difficult decisions" she has made.

"Growing up in a large Mexican-American family in La Puente, California, I never imagined that I would have the opportunity to serve in a president's Cabinet, let alone in the service of such an incredible leader," said Solis.

She said she was proud of her tenure at the department during a time which saw unbearably high unemployment rates.

"We have much to be proud of," she said. "In the past four years, more than 1.7 million people have completed federally-funded job training programs; of those, more than one million have earned industry-recognized credentials. In addition, Labor Department investments in our community colleges have expanded their capacity to provide local, flexible, employer-specific job training to millions of Americans, and transformed these institutions into engines of economic growth.

She also touted the department's work overseeing parts of the controversial 2009 stimulus program, unemployment insurance and mine safety.

Her departure leaves President Obama with one less woman in his cabinet - two cabinet his replacement picks announced over the past few weeks have been white men.

President Obama issued a short statement praising her four years of service.

"Over her long career in public service - as an advocate for environmental justice in California, state legislator, member of Congress and Secretary of Labor - Hilda Solis has been a tireless champion for working families," said Obama in a written statement issued by the White House.

"Over the last four years, Secretary Solis has been a critical member of my economic team as we have worked to recover from the worst economic downturn since the Great Depression and strengthen the economy for the middle class. Her efforts have helped train workers for the jobs of the future, protect workers' health and safety and put millions of Americans back to work. I am grateful to Secretary Solis for her steadfast commitment and service not only to the Administration, but on behalf of the American people. I wish her all the best in her future endeavors."

Solis was the first Hispanic woman to serve in a presidential cabinet.

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