Nissan Motor Co. slashed its full-year profit forecast to its lowest in nearly a decade due to weakness in the United States, just as it adjusts to life without Carlos Ghosn and charts its future with alliance partner Renault SA.

The automaker expects operating profit for the year ended March to drop 45 percent versus a year earlier to ¥318 billion ($2.84 billion), from a previous forecast for ¥450 billion, on expenses related to extending vehicle warranties in the United States, its biggest market.

In a statement on Wednesday, Nissan said sales had taken a hit in the aftermath of the arrest of former Chairman Ghosn, contributing to a decline in profit to its lowest since the year ended March 2010.