The Commission for Communications Regulation (ComReg) has recommended that RTÉ's transmissions wing operates "in a transparent and non-discriminatory fashion" in the provision of broadcasting services.
In a study of the market, the results of which were published yesterday, ComReg concluded that RTÉ Networks was "dominant" in the national transmission of analogue terrestrial radio and television.
The regulatory body did not investigate whether RTÉ Networks had discriminated against competing broadcasters when operating transmission capacity.
But it said that, having assessed the level of competition in the market, it would pursue any complaints of such discrimination in the future.
TV3 last year initiated a complaint with the Department of Communications against RTÉ, claiming it was being charged three times more than TG4 for its transmission service despite receiving less capacity.
But details of the complaint had not been forwarded to ComReg, whose study formed part of a major review of domestic broadcasting and mobile markets as required by the European Commission.
In a statement yesterday, RTÉ said its transmissions division was "already operating in a non-discriminatory and transparent fashion", and therefore ComReg's proposed obligation on the matter "presents no difficulty".
RTÉ Networks Ltd, which was recently created by the State broadcaster as part of a failed bid to sell off its transmission network, has promised to start publishing an annual rate card for the provision of services and infrastructure.
RTÉ said the division would also from this year "maintain a schedule of tariffs for analogue and digital broadcast services, which will be reviewed annually and approved by the board of RTÉ Networks Ltd before September 30th each year".
Welcoming the report, TV3's director of legal affairs, Mr David McMunn, said: "We have long stated that RTÉ was in a dominant position, and that the pricing issue needs to be addressed. That appears to be happening now."