Taiwan-based mobile handset manufacturer HTC has agreed to pay royalties to Microsoft for HTC phones running Google's Android mobile operating system, the US software giant said.

Microsoft, which licenses its own Windows Mobile operating system to handset manufacturers around the world, did not identify any specific patents at issue in the HTC phones or the amount of the royalties it will receive from HTC.

It said the patent agreement "provides broad coverage under Microsoft's patent portfolio for HTC's mobile phones running the Android mobile platform."

"Microsoft has a decades-long record of investment in software platforms," Horacio Gutierrez, Microsoft's deputy general counsel of intellectual property, said in a statement late Tuesday.

"As a result, we have built a significant patent portfolio in this field, and we have a responsibility to our customers, partners, and shareholders to ensure that competitors do not free ride on our innovations," Gutierrez said.

He said Microsoft has adopted "a proactive approach to licensing to resolve IP infringement by other companies, and have been talking with several device manufacturers to address our concerns relative to the Android mobile platform."

The open-source Android platform of Microsoft rival Google powers a number of mobile phones made by HTC including the Nexus One, the smartphone launched by Google in January.

Apple, maker of the popular iPhone, filed a lawsuit against HTC on March 2 accusing the Taiwan company of infringing on 20 iPhone patents. HTC has said it will "fully defend" itself against the Apple charges.

HTC, which stands for High Tech Computer Corp., is Taiwan's leading mobile phone manufacturer.