Cellphone maker HTC Corp. signed a licensing deal to use Microsoft Corp.’s patents in handsets powered by Google Inc.’s Android software, as another big rival steps up legal pressure on Google in the mobile business.

Microsoft believes Android infringes on a range of the company’s patents covering user interfaces and other aspects of mobile operating systems. Under the deal, HTC of Taiwan will pay Microsoft an undisclosed amount to use the software giant’s intellectual property in phones running Android.

“We have consistently taken 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,” Horacio Gutierrez, deputy general counsel of intellectual property and licensing for Microsoft, said in a statement.

A spokesman for Google declined to comment.

The Microsoft deal is another sign of the growing legal pressure competitors are putting on Google, a company that has seen impressive growth in its share of the mobile market in recent months. Apple Inc. has sued HTC over 20 hardware and software patents it alleges the handset maker is illegally using in its Android phones in what many see as an indirect attack on Google. HTC has said it will fight Apple’s allegations.

“The big guys are using their patents to align their interest and stake their claims in the marketplace,” said Mark Kesslen, an intellectual property lawyer for Lowenstein Sandler PC.

An HTC spokeswoman said the company “licenses technology from a variety of companies as a standard practice” in the mobile industry. “This is no different,” she said.

The share of Android-based smartphones in use by U.S. consumers leapt to 9% in February from 4% in November, according to comScore Inc. Apple’s iPhone remained nearly flat during that period at 25% of the market, while phones using Microsoft software fell to 15% in February from 19% in November.

While HTC makes Android phones, it’s also one of Microsoft’s most important mobile partners. HTC is expected to be an important handset partner for Microsoft as it seeks to turnaround its mobile business with the launch of a new operating system, Windows Phone 7, this holiday season.

HTC manufactures the high-profile Google phone, dubbed Nexus One, and is also behind other Android devices like Sprint Nextel Corp.’s Evo and the recently announced Droid Incredible, which many consider Verizon Wireless’s latest flagship device. Verizon Wireless is jointly owned by Verizon Communications Inc. and Vodafone Group PLC.