British Telecommunications PLC (BT) and T-Mobile International AG have joined an Asian consortium called the Wireless Broadband Alliance (WBA), which plans to be operating more than 26,000 Wi-Fi hotspots around the world by the end of this year.

BT and T-Mobile join China Netcom Communications Group Corp. (China), Korea Telecom Corp., Maxis Communications Bhd. (Malaysia), StarHub Pte. Ltd. (Singapore), and Telstra Corp. Ltd. (Australia) in the alliance, which operates around 13,000 hotspots now.

T-Mobile’s units in both the U.K and U.S. will be involved in the alliance, according to a WBA statement Wednesday.

The original alliance members, except for Korea Telecom, have begun a pilot trial for international Wi-Fi roaming in their four countries at over 500 Wi-Fi hotspots. Korea Telecom is expected to open its hotspots to international roamers by the end of the year as well.

There will be no extra charge for international Wi-Fi roaming during the trial, which will continue until the end of October. Telstra currently charges a minimum of A$5 (US$3.25) for the first 15 minutes of use and A$0.20 per minute after that.

Formed in March, the WBA has said its intention is to build a global Wi-Fi network under a single brand identity, utilizing a common technology platform.