Nokia (NOK) - Get Report shares fell more than 14% in morning trading in Finland after it reported a sharp fall in quarterly earnings and warned about tough market conditions.

Nokia shares were marked 14.67% lower, changing hands at €4.35, and were on track for their worst fall since February 2016. The telecom company's American Depository Receipt was down more than 15% in premarket trading.

Nokia on Thursday reported network sales were down 9% in the third quarter to €4.8 billion ($5.7 billion), "reflecting challenges related to market conditions and certain projects in Mobile Networks, primarily in North America and Greater China," the company said. Operating profit in the business dropped 23% to €334 million, against analyst expectations of €432 million.

The group posted a 7% decline in net sales for the three months to end September compared with the same period a year ago.

CEO Rajeev Suri said operators' consolidation and technology transitions were slowing demand, while competition in China had toughened.

"The early positioning for 5G is well underway in that country and the cost of gaining or even maintaining footprint is significant ... We want to ensure the right long-term footprint, but not at any cost," Suri told a conference call.

Nokia estimated a global market decline of between 4% and 5% for full-year 2017, compared with a previous forecast of 3% to 5%, and a 2% to 5% year-on-year fall in 2018.

More of What's Trending on TheStreet: