The US International Trade Commission (ITC) is going ahead with the invetigation against against chip maker Qualcomm for alleged patent infringement.

Mobile phone manufacturer Nokia filed the complaint last month requesting ITC to ban US imports of certain Qualcomm chipsets that infringe Nokia patents.

A Nokia spokeswoman said the company believes there is significant evidence that Qualcomm has copied patented technology without permission.

Nokia and Qualcomm have been in a legal dispute after part of a 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.

Nokia filed the complaint to ITC last month as a response to Qualcomm's ITC case filed in June 2006. ITC opened a hearing in that case last week.