BANGKOK -- Gulf Energy Development, an up-and-coming Thai conglomerate known for its power generation business, on Monday proposed a buyout of InTouch Holdings, the largest shareholder of Advanced Info Service, the kingdom's largest mobile operator. Gulf Energy, which held an 18.93% stake in InTouch as of Friday, plans to buy the rest of the telco's issued shares at 65 baht each. The Bangkok-based company will have to prepare 169 billion baht ($5.4 billion) to acquire the 2.6 billion shares. InTouch, which is also the largest shareholder of satellite company Thaicom, was formerly known as Shin Corp.