Zetsche and Chrysler CEO Tom LaSorda thanked workers for their service in an e-mail message and urged continued relationship with Mercedes, the Detroit Free Press said.
They said they would embark soon "on new and promising futures as two separate companies."
People familiar with the e-mail described it as a good-bye from Zetsche, the Free Press said.
DaimlerChrysler plans to sell 80.1 percent of Chrysler to Cerberus Capital Management, a private equity firm, but work together on several projects such as diesel, hybrid and fuel cell technology and electrical component development.
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