Citigroup is facing a potential multibillion-dollar write-down as it begins unwinding its minority investment in the Morgan Stanley Smith Barney brokerage, the Wall Street Journal reported on its Web site.

Morgan Stanley has the right this spring to start buying Citigroup out of the joint venture formed in 2009. Price is likely to be one of the main issues on the bargaining table when negotiations begin this spring, people familiar with the situation told the Journal.