NEW YORK —MetLife is in talks to part ways with the life insurance agents who long defined one of the world’s biggest life insurance companies.

The unit that the company is negotiating to sell, known as MetLife Premier Client Group, has 4,000 agents who sell a number of policies, including life insurance, to individuals and small businesses, according to a Securities and Exchange Commission filing. The New York company also sells insurance in other ways, including through independent agents and brokerage agencies. It has a total of 69,000 employees.

The company confirmed Thursday that it was negotiating a possible sale with MassMutual, another insurance company, after talks were first reported by The Wall Street Journal.

The nation’s largest insurance companies began to restructure their businesses following the financial crisis, from which the term “too big to fail” arose. New regulations intended to head off economic calamities have pushed companies like MetLife into major overhauls. AIG, for example, has cut its business operations and is in the process of selling its dealer-broker segment and spinning off its mortgage-insurance division.

Last month, MetLife said it planned to spin off a substantial portion of its life insurance business into a separate company because of greater government oversight.