Customs and Border Protection (CBP) Commissioner Alan Bersin has announced his resignation effective December 30. Deputy Commissioner David V. Aguilar is slated to serve as Acting Commissioner.

In a statement announcing his resignation, Bersin said he was grateful for the chance to lead CBP.

“My service as commissioner has been one of the most rewarding experiences of my public life,” Bersin said Thursday. “I am immensely proud of the significant and meaningful achievements we have made on our borders and at our nation’s ports of entry over nearly two years.”

Bersin’s recess appointment term expires Dec. 31.