Nokia posted a fourth-quarter net loss of (euro) 1.07 billion ($1.38 billion) as sales slumped 21 per cent even as the company's first Windows smartphones hit markets in Europe and Asia.
The loss compares with a profit of (euro) 745 million in the same period a year earlier.
Nokia said net revenue fell to (euro) 10 billion, from (euro) 12.6 billion in the fourth quarter of 2010, with smartphone sales plunging 23 per cent.
Nokia has lost its once dominant position in the global smartphone market, with Android phones and iPhones overtaking it in the growing smartphone segment.
The Finnish company is attempting a comeback with phones using Microsoft's Windows software, and said it has sold "well over'' 1 million such devices since they hit the stores in November in Europe and Asia, and the US in January.