BERLIN, Dec 13 (Reuters) - Porsche SE, the

holding company which owns a third of Volkswagen,

expects an impairment on its investment in the carmaker of up to

20 billion euros ($20.98 billion), it said on Friday.

It also expects an impairment on its investment in luxury

carmaker Porsche AG of up to 2 billion euros, based on analyst

expectations for the two companies.

($1 = 0.9534 euros)