By Monica Houston-Waesch

FRANKFURT--German retailer Metro AG (MEO.XE) Friday warned investors of a goodwill impairments amounting to 450 million euros ($483.6 million) this year, but said this won't cause a revision its outlook for profit before one-offs.

The goodwill adjustment will reposition the retailer group's Real hypermarket chain and relates to the acquisition of companies for the unit 17 years ago.

Metro is still projecting group earnings before interest, tax and special items to be slightly above the EUR1.73 billion posted in the fiscal year to Sept. 30, 2014.

Metro said it will continue to invest in modernization, store infrastructure and merchandise presentation at its Real hypermarkets, adding that 82 of more than 300 stores have been modernized.

Write to Monica Houston-Waesch at nikki.houston@wsj.com

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