Britain's Vodafone Group PLC announced Wednesday that it will purchase rival British Telecommunications PLC's shares in Japan Telecom Co., making it the top shareholder of the Japan's third largest telecommunications operator.

The deal, which will involve the sale of BT's shares in Japan Telecom and its wireless subsidiary for 652.3 billion yen, will be completed by the end of August.

The transaction will leave Vodafone holding a 45 percent stake in Japan Telecom and 46 percent of J-Phone Communications Corp., the holding company of Japan Telecom's mobile units.