A planned merger of True Corp and dtac ran into an unexpected obstacle, with the supervisory committee of the regulator urging the body to block the tie-up, which would create an operator controlling more than half of the country’s mobile connections, Nikkei Asia reported.

The so-called super board, which oversees the National Broadcasting and Telecommunications Commission (NBTC), submitted a letter to the watchdog’s head highlighting competitive concerns and suggesting the merger be halted, the news agency wrote.

Bangkok Post reported an extraordinary House committee is also studying the impact of the merger, with its findings due to be released by end-April.

The proposed tie-up was announced in November 2021 and was expected to receive speedy approval by regulators. Insiders reckoned the country’s largest private company Charoen Pokphand Group, which owns True, was unlikely to face resistance despite concerns.

Somkiat Tangkitvanich, president of the Thailand Development Research Institute, in December 2021 accused the regulator of “failing to do its job” by not opposing the deal.

Last week the operators announced they would hold a joint shareholders’ meeting on 4 April.

The boards of both companies approved the deal in mid-February, when they filed a merger notification with the regulator.

They expected the merger to close by September.