Department of Homeland Security Secretary Janet Napolitano will resign her post in September, The Daily Caller has learned.

In a statement released Friday, Napolitano expressed her gratitude to President Obama for her over four years in the post.

“For more than four years I have had the privilege of serving President Obama and his Administration as the Secretary of Homeland Security,” Napolitano said. “The opportunity to work with the dedicated men and women of the Department of Homeland Security, who serve on the frontlines of our nation’s efforts to protect our communities and families from harm, has been the highlight of my professional career.”

“We have worked together to minimize threats of all kinds to the American public. The Department has improved the safety of travelers; implemented smart steps that make our immigration system more fair and focused while deploying record resources to protect our nation’s borders; worked with states to build resiliency and make our nation’s emergency and disaster response capabilities more robust; and partnered with the private sector to improve our cybersecurity,” she continued.

In a statement, Obama praised Napolitano for her “outstanding work.”

“I want to thank Secretary Napolitano for her outstanding work on behalf of the American people over the last four years. At the Department of Homeland Security, Janet’s portfolio has included some of the toughest challenges facing our country. She’s worked around the clock to respond to natural disasters, from the Joplin tornado to Hurricane Sandy, helping Americans recover and rebuild. Since day one, Janet has led my administration’s effort to secure our borders, deploying a historic number of resources, while also taking steps to make our immigration system fairer and more consistent with our values,” Obama said. “And the American people are safer and more secure thanks to Janet’s leadership in protecting our homeland against terrorist attacks. I’ve come to rely on Janet’s judgment and advice, but I’ve also come to value her friendship. And as she begins a new chapter in a remarkable career of public service, I wish her the best of luck.”

Napolitano is slated to become the next president of the University of California system.

“After four plus years of focusing on these challenges, I will be nominated as the next President of the University of California to play a role in educating our nation’s next generation of leaders,” Napolitano said. “I thank President Obama for the chance to serve our nation during this important chapter in our history, and I know the Department of Homeland Security will continue to perform its important duties with the honor and focus that the American public expects.”

Napolitano is expected to more than triple her salary, from about $200,000 to the $601,000 gross pay earned by the University of California’s current president, Mark Yudof.

Ariel Cohen and Gabe Finger contributed to this report.

This article has been updated.

Correction: Napolitano announced her resignation Friday, but will step down in September.

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