After years of delays, Thailand's top three mobile telephone operators will bid next week for licences to provide third-generation (3G) services in the kingdom, regulators said Tuesday.

A business dispute meant that as other nations move to introduce faster 4G technology, Thailand has yet to roll out a proper 3G service, more than a decade after it was first launched in Japan.

Leading telecom firms Advanced Info Service, Total Access Communication (Dtac) and True Move have qualified to bid at a 3G licence auction on October 16, the National Broadcasting and Telecommunications Commission announced.

A total of 45 megahertz of bandwidth will be on offer, with a minimum price of 4.5 billion baht ($147 million) for each five megahertz block.

In 2010 a Thai court halted a 3G licence auction at the last minute after state-owned telecoms giant CAT argued that the then-regulator, the National Telecommunications Commission, had no authority to conduct the bidding.

The slow pace of progress has frustrated smartphone users.

"I bought my iPhone partly because I wanted to have 3G as I like checking emails and surfing the Internet," said 37-year-old assistant manager Siwaporn Bunthuwanich.

"Other countries are more advanced but we're still left behind. The signal is not even stable yet. It makes me wonder whether we're a developing or undeveloped country," she said.

One mobile operator, Dtac, is already looking further ahead by starting a technical trial of 4G in part of Bangkok. It expects to complete a nationwide network update by the end of 2012 to prepare for an eventual official launch.