The Independent Television Commission, which awarded the licence to Freeview in July, is looking at the issue of how many channels will be carried on the service, which will be free to consumers who already have a set-top box or who buy a specially produced one at £99.
Channel 4 and ITV are pushing for more channels to be broadcast. However, Freeview argues that it will be able to offer better broadcast quality with fewer channels. One of the problems that dogged the failed ITV Digital was reports of poor reception.
Channel 4 and ITV made their calls in submissions to the ITC late last week.
In a statement, ISBA said: "Naturally, advertisers are keen that commercial channels are well represented on the platform, especially given that an expanded BBC, offering several new digital channels, threatens to dominate it."
Last week, it was reported that the launch of Freeview would be delayed until next year, after channel operators bidding to be carried on the service reportedly had not heard back about their bids. However, this has been denied by Freeview.
If you have an opinion on this or any other issue raised on Brand Republic, join the debate in the .