The initial public offering (IPO) could become one of Europe's and Germany's largest floats in years, with the listing valuing the luxury car brand between €60bn ($60bn, £51bn) to €85bn.
VW which triggered the plan late on Monday, is planning the float at the end of this month or at the start of October, but the group's supervisory board said this was "subject to further capital market developments".
On Tuesday, Porsche's chief financial officer Lutz Meschke said the debut of the Stuttgart-based subsidiary will only backtrack in the event of severe geopolitical problems that would make the importance of a listing fade in comparison.
"You never know what will happen regarding geopolitical issues, but if a potential IPO would be stopped now, we are talking about severe problems," he told reporters on a media call. "By then a potential IPO would not be a real issue."
VW said it would use the proceeds to accelerate the company's transition to electric vehicles and self-driving cars.
Shares in Volkswagen were up 3.6% in mid-morning trade in Frankfurt on Tuesday.
Volkswagen chief executive Oliver Blume said the listing could break the ice for capital markets starved of potential investments.
"There is a lot of capital in the market," he said. "We think the Porsche IPO could be an icebreaker.
As a luxury car brand with premium prices, Porsche is VW's moneymaker. The sports car's operating profit shot up 22% in the first half of 2022, compared to a 8% fall in the mass market-oriented Volkswagen brand.
VW, which first revealed plans for the IPO in February, plans to sell 12.5% of Porsche directly to new investors.
It added that the Qatar Investment Authority, one of the carmakers largest shareholders "has expressed strong interest" in buying 4.99% of the slice.
With the share sale, the billionaire Porsche-Piëch families are set to regain direct influence over what used to be their business, around 13 years after the clan was forced to sell the sports car division to Volkswagen.
The clan's investment company Porsche Automobil Holding SE would emerge with a blocking minority stake of 25% plus one share.
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