UPDATE 1-Time Warner mulls sale of U.S. AOL access business

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NEW YORK, Sept 18 (Reuters) - Time Warner Inc (TWX.N), the world's largest media company, will "look hard" in the next 12 to 18 months at possibly selling off its AOL dial-up Internet access business, similar to its strategy in Europe.

AOL, which restructured last year to offer most of its services for free, aims to focus exclusively on boosting online advertising sales both on its AOL.com portal and across the Web.

Chief Executive Richard Parsons said the idea, which it has explored in the past, was difficult as its access business continues to contribute traffic to its AOL.com portal.

"It's much more complicated here than in Europe," Parsons told investors attending the Goldman Communicopia media conference in New York on Tuesday.

AOL said on Monday it would realign its advertising business to create a third-party online advertising network powerhouse as marketers are looking to advertise across the Web rather than focus budgets on any one portal such as AOL.com.

The company also announced on Tuesday it planned to move the online division's headquarters to New York, the U.S. advertising capital, to focus on building its ad network.

Some investors and Wall Street analysts have called for the sale or spin off of AOL, the complete divestiture of Time Warner Cable (TWC.N), and the sale of its publishing company, from which its name is derived, as a way to resuscitate its sluggish stock price.

"The focus right now is let's see if we can build it," Parsons said of AOL.

Addressing calls for a breakup of Time Warner, he said, "We would like to see if the whole is greater than the sum of its parts, which I believe it to be." (Reporting by Kenneth Li)