Mobile phones giant Vodafone has joined 13 other top telecom and chipmaking companies in an alliance to support Google's new phone platform.

Other companies signing up include technology firm ARM Holdings and Sony Ericsson. The Open Handset Alliance has been formed to contribute to Google's Android mobile device platform, which it hopes will rival Apple's iPhone.

Sony Ericsson is expected to be the first company to introduce a mobile device by the middle of next year. The platform for smartphones will take on rivals that use open-source Linux software, such as Nokia-owned software maker Symbian.

Asustek of Taiwan, Toshiba and Garmin also pledged their support, bringing the number of companies in the alliance to 47.

Earlier members of the Alliance include chipmaker Intel and mobile phone makers Motorola and Samsung.

"Android is set to become a significant application framework for mobile phones," said Ericsson's Robert Puskaric.

Each member of the alliance has agreed to develop applications and services or design Android-compatible devices.

Google and Apple have wooed developers to create applications for their mobile devices, but Apple keeps a tight grip on the iPhone's hardware and operating software.

Android's biggest competitor is Symbian, which controls half the market.