Citigroup became the first giant United States bank to definitively tee up a takeover of its leadership by a woman on Thursday, when it named Jane Fraser, a 15-year veteran of the firm, as its president.

The elevation of Ms. Fraser puts her in line to eventually succeed Michael Corbat as chief executive.

“In many ways, Jane helped shape the company we are today,” Mr. Corbat said in an email to employees announcing the change.

Ms. Fraser will also become chief executive of Citi’s global consumer banking business, serving alongside Paco Ybarra, the head of Citi’s institutional business. Granting her the title of president, however, was a clear sign that she was in line to take over for Mr. Corbat.