Hogan, 46, announced his action in a memo sent on Friday to employees in his department and reviewed by Reuters.

"I'm looking forward to taking this time off to spend with my family and friends," Hogan wrote, adding that he had discussed the possibility of a leave with CEO Jamie Dimon and other members of the company's operating committee "over the past few months."

Hogan's father died in November after a long illness, according to a person close to the bank.

Hogan said that Ashley Bacon, deputy chief risk officer, will lead the risk management group and report to Dimon until he returns.

Hogan was promoted to his post in January 2012 and was just becoming acquainted with the operations of the company's Chief Investment Office when trading losses there began to mushroom, according a 129-page investigative report released by the company on January 16.

Before that job, Hogan had been chief risk officer of the company's investment bank since 2006.

In recent months, Hogan has worked on the overhaul of the company's risk management systems, which have come under the scrutiny of the company's directors and regulators.

JPMorgan lost $6.2 billion on the derivatives trades, which are known by the nickname, "London Whale," which hedge funds gave to the trader who made them because they were so big.

(Reporting by David Henry in New York. Editing by Andre Grenon)