AOL, the Time Warner Inc. Web unit will start selling and managing Internet ads for Verizon Communications Inc., as it continues to diversify its business and put much focus to advertising.

AOL said its Platform A sales network will handle display and video ads for Verizon, which will continue to use AOL's Third Screen Media technology to manage the sales of its ads for mobile devices.

Under the agreement, AOL will be the sole company that will guarantee Verizon ads to Web sites.

According to ComScore, a research company, the Platform-A network - which currently buys and sells ads for Volkswagen AG and Papa John's International Inc. - helped AOL's ad business increase to 90 percent of the 185 million Internet users in the U.S. during February.

Verizon is currently the second biggest U.S. phone company.