Nokia saw its net loss increase three-fold in the second quarter of 2012 in year-on-year terms, as its smartphone sales continue to face tough competition from rivals Apple and Samsung.
Nokia's net loss reached €1.41 billion, compared to a figure of €368 million during the same quarter of 2011.
The Finnish firm's total sales dropped by 19 percent to reach €7.54 billion, while its smartphone sales fell 34 percent to €1.54 billion.
The leading mobile phone manufacturer around the globe for more than 10 years, Nokia was usurped by Samsung during the first quarter of 2012, research company Gartner recently announced.
Nokia's chief executive officer, Stephen Elop, said: "Nokia is taking action to manage through this transition period.
"While Q2 was a difficult quarter, Nokia employees are demonstrating their determination to strengthen our competitiveness, improve our operating model and carefully manage our financial resources."
Julian Jest, research analyst for handsets and devices at Informa Telecoms & Media, added: "Nokia has received criticism for relying too much on the Windows Phone platform. While there are other options, such as using the Android OS, Nokia is right to persevere with the Windows Phone OS.
"Lumia sales have picked up in 2012, particularly in North America, a key market in which Nokia has struggled in recent times. As a stand-alone OS, Windows Phone will not succeed, and will remain a niche product.
"However, Microsoft has a huge market share in terms of desktop computers, laptops and Ultrabooks. The release of Windows 8 across multiple platforms, including the new Surface tablet, will provide the consumer with more exposure to OS's unique features and benefits, and will give the boost in sales that Nokia needs."
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