(CNN) - Beau Biden said Thursday he won't seek re-election this year as Delaware attorney general and plans instead to run for governor in 2016.
"Over the past few months, as I've been planning to run for reelection, I have also been giving a great deal of thought to running for Governor in 2016," he said in a statement. "What started as a thought-a very persistent thought-has now become a course of action that I wish to pursue."
Beau Biden, 45, is Vice President Joe Biden's eldest son. He was elected as Delaware attorney general in 2006.
"After careful consideration, I have concluded that it is not right to ask for your support in 2014, knowing that my focus would be divided between doing my job as Attorney General while at the same time running as a candidate for Governor," he said.
Questions have been raised about his health, however, since he underwent a procedure in August at a Houston hospital after feeling weak and disoriented on a family vacation. He made few public appearances in the months following the procedure.
In 2010, he suffered what doctors said was a mild stroke. His speech and motor skills were not affected.
His announcement Thursday came only in written form - sent out in an email to supporters and posted to his website. He did not hold a press conference, and he has not spoken publicly about his decision in an interview.
He served in Iraq for one year as a captain with the Delaware Army National Guard. Biden acted as a prosecutor in the U.S. attorney's office in Philadelphia from 1997 to 2002.
He and his wife, Hallie, have two children.
CNN's Dana Davidsen, Steve Brusk, and Ashley Killough contributed to this report.