Regulators will advise pay-TV operators by letter that they are to be prohibited from carrying Channel 3's analogue signal.
It may take 15 days from Sept 3 before the ban takes effect, said Supinya Klangnarong, a member of the National Broadcasting and Telecommunications Commission's broadcasting committee, after a meeting with representatives from Channel 3 and 24 digital-TV operators on Wednesday.
In the interim, Channel 3's analogue broadcasts will remain on pay-TV platform so viewers will not be affected, said Col Natee Sakonrat, chairman of the committee.
Ms Supinya said the broadcasting committee has full authority to deal with the Channel 3 issue.
"The junta clarified its No.27 order - it has nothing to do with regulating the broadcasting industry and has told us to deal with it," she said.
"Channel 3 should stop quoting the order and compete in the digital TV business. We're ready to clear all legal hurdles so it can simulcast," she said.
Ms Supinya said she would help Channel 3 sort out issues such as redundant timeslots and different juristic persons operating its analogue and digital businesses .
Channel 3 sent two lawyers with no decision-making authority to Wednesday's meeting.
"We're confident Channel 3 is ready to broadcast digitally. After all, it won three channels in the [digital-TV] auction for the highest price of 6 billion baht," Col Natee said.
"It's better that we settle our differences on our own than go to court," he said.
Polchai Vinijchaikul, executive vice-president of Mcot Plc, the owner of Channel 3's concession, said MCOT was open to amendments to its contract if it helped the digital-TV industry move forward.