AMSTERDAM (Reuters) - Dutch bancassurer ING Groep said on Tuesday it will sell three of its U.S. independent broker-dealer units to private equity firm Lightyear Capital LLC as it restructures its operations worldwide.

Terms of the deal, which is expected to close early next year, were not disclosed.

The sale follows ING's market-shaking announcement last week that it will split in two and raise 7.5 billion euros ($11.08 billion) from shareholders as part of a restructuring plan negotiated with the European Commission.

The three broker-dealers to be sold are Financial Network Investment Corp., Multi-Financial Securities Corp. and PrimeVest Financial Services Inc. Lightyear said the three, combined, had gross revenues of about $653 million for the year to June 30.

ING said it will keep two broker-dealers -- ING Financial Advisers of Windsor, Conn. and ING Financial Partners of Des Moines, Iowa -- as they are aligned with ING's product strategy in the United States.

"It is also in the best interest of the broker-dealers, their employees, and the affiliated representatives and financial institutions, to find a new ownership structure," ING Insurance management board member Tom McInerney said in a statement.

(Reporting by Ben Berkowitz; Editing by Mike Nesbit)