The world's top cellphone maker Nokia said on Saturday it would defend itself vigorously against Apple's complaint to United States International Trade Commission, filed on Friday. Nokia will study the complaint when it is received and continue to defend itself vigorously, said a company spokesman.

However, this does not alter the fact that Apple has failed to agree appropriate terms for using Nokia technology and has been seeking a free ride on Nokia's innovation since it shipped the first iPhone in 2007, he said.

The two phone giants are in the midst of a major legal battle, which started last October when Nokia charged Apple for using its patented technologies without paying for them.

Nokia has stumbled badly in the fast-growing smartphone sector and relative newcomer Apple has gained ground against the market leader thanks to the iPhone, but still trails Nokia in smartphones sales.

Apple, which entered the industry in mid-2007, overtook Nokia in the September quarter as the cellphone maker generating the highest total operating profit.

The legal dispute, potentially involving hundreds of millions of dollars in annual royalties, reflects the shifting balance of power in the mobile industry as cellphones morph into handheld computers that can play video games and surf the Web.

(Reporting by Tarmo Virki; editing by Patrick Graham)

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