Nokia said on Friday it had asked the U.S. International Trade Commission (ITC) to bar the import of some Qualcomm Inc chipsets to the United States, alleging they are infringing five Nokia patents.

The patents in question relate to technologies that improve the performance and efficiency of wireless communication devices as well as enabling lower manufacturing costs, smaller product size and increased battery life, Nokia said.

Nokia, which makes more than one in three cellphones sold globally, said Qualcomm uses Nokia's patents in certain GSM/WCDMA and CDMA2000 chipsets.

These technologies are important to Nokia's success as they allow its products to have competitive advantages over those of competitors, Nokia said.

A legal row between the two firms has continued since part of a cross-licensing deal over technology patents expired on April 9. Their increasingly bitter fight is worrying investors and the industry on both sides of the Atlantic.

The dispute centers on Nokia's use of Qualcomm patents for high-speed 3G wireless technology, but it also has a bearing on Qualcomm's chips business, which Nokia says uses many Nokia-patented technologies.

Analysts estimate Nokia has paid Qualcomm about $500 million per year and wants to reduce this cost. Nokia says its patent portfolio is much stronger now than 15 years ago, when the original cross-licensing deal was signed.

Industry players and analysts alike expect any licensing agreement between the two to have a major impact on the future of 3G technologies.

Qualcomm has also been fighting over patents with rival Broadcom Corp., with ITC ruling against Qualcomm in that dispute, banning imports of new advanced phones using chips the ITC said infringed on Broadcom patents.

In June 2006 Qualcomm filed a complaint against Nokia with ITC regarding six GSM patents, but the judge has put the case on hold indefinitely.