(Reuters) - Wells Fargo ( WFC ) Chief Executive Officer Charlie Scharf said on Thursday that the U.S. lender may lose $2 billion to $3 billion on its commercial real estate office loan portfolio.

"We've reserved for all of it, so the balance sheet is de-risked, but it's going to play out over three, four years," Scharf said at an event.

(This story has been refiled to add the dropped word 'to,' in the headline)