Microsoft has filed a patent infringement suit against GPS system vendor TomTom.

The decision to file suit in a Washington State district court came after more than a year of fruitless attempts by Microsoft to strike a deal with TomTom over the use of what Microsoft claims are patents relating to navigation technology.

"In situations such as this, when a reasonable business agreement cannot be reached, we have no choice but to pursue legal action to protect our innovations and our partners who license them," said Horacio Gutierrez, corporate vice president and deputy general counsel for intellectual property and licensing at Microsoft.

"Other companies that utilise Microsoft patents have licensed them, and we are asking TomTom to do the same."

TomTom has reportedly said that it will "vigorously" defend itself against the charges.

Gutierrez added that Microsoft has not abandoned hope for a deal out of court, and will continue to seek a licensing agreement with TomTom.

Licensing of intellectual property has been a hot-button issue for Microsoft in recent years. Aside from its landmark 2005 anti-trust agreement, and subsequent struggles to comply with regulatory boards on intellectual property licensing, the company has sought out patent-sharing deals with such companies as Novell and Nikon.