Blythe Masters, JP Morgan Chase's high-profile commodities chief, is resigning following the announced sale of the bank's physical-commodity unit, according to an internal memo obtained by The Wall Street Journal.

"Blythe Masters has informed us of her intention to leave the firm, take some well-deserved time off and consider future opportunities," according to the memo, which was signed by JP Morgan chief executive James Dimon and Daniel Pinto, chief executive of JP Morgan's investment bank.