NEW YORK (TheStreet) -- Volkswagen (VLKAY) appointed Matthias Müller as CEO, effective immediately, after Martin Winterkorn resigned on Wednesday after the company admitted to cheating emissions tests.

Müller will also continue his role as chairman of Porsche until a successor is named.

"My most urgent task is to win back trust for the Volkswagen Group — by leaving no stone unturned and with maximum transparency, as well as drawing the right conclusions from the current situation," Müller said in a statement.

"Under my leadership, Volkswagen will do everything it can to develop and implement the most stringent compliance and governance standards in our industry," he added.

Volkswagen's board also announced a new corporate structure that will be more streamlined.

Volkswagen decided to combine its operations in the U.S., Mexico and Canada under one North American division, led by Winfried Vahland, formerly Škoda's chairman.

Michael Horn will remain president and CEO of Volkswagen Group of America.

Volkswagen stock is falling by 4.49% to $25.94 on heavy trading volume on Friday afternoon.

Insight from TheStreet's Rating Team

TheStreet's Jim Cramer, portfolio manager of Action Alerts PLUS charitable trust portfolio, commented on Volkswagen's emissions scandal on Real Money. Here's what he had to say about the company:

Continuing my series of Nothing's Working, have you noticed that the problems at Volkswagen are spilling over to hurt all automakers? While there is some concern that tests may have overstated the emissions of BMW's engines, the simple truth is what's bad for the goose is good for the gander -- in this case every other automobile company in the world.

Let's face it, there is simply no way that VW isn't in total disarray and there is no way that its sales can hold up at all.

But is that going to stop people from buying cars, or is it going to stop people from buying Volkswagens and instead choose other cars, especially if the opportunity to buy Volkswagens is taken away by government action?

-Jim Cramer's "Volkswagen's Mess Is Good for Competitors, Right?" originally published on 09/24/15 on Real Money.

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