The networks say the camera ban is unconstitutional
At a hearing in Alexandria, Virginia, attended by the suspect, Zacarias Moussaoui (33), a lawyer for the cable network Court TV argued in favour of live coverage of the trial, while a representative for the US Justice Department opposed such a move.
Mr Moussaoui, a French citizen of Moroccan decent, also backs a television trial.
His lawyer re-iterated that broadcasting the proceedings would provide "an added layer of protection" in guaranteeing a fair trial.
Cameras are banned in federal criminal trials in the United States.
Court TV, a division of AOL Warner, has called the ban unconstitutional and petitioned the court to allow in the cameras.
The cable network is supported by major American media organisations like CNN, NBC, CBS, and ABC.
"The entire nation has a direct interest in these proceedings, if not the entire world", said Court TV's lawyer Lee Levine in the half-hour hearing.
'Chilling problem'
But Elizabeth Collery of the US Justice Department said the government was concerned that witnesses' testimony would be affected if they knew they were on live television.
That, in turn, could affect the jurors, she said.
Judge Leonie Brinkema said she was also concerned about the security of witnesses and other trial participants.
Having not only television pictures but permanent images of witnesses, the judge and others on the internet long after the trial "could be a chilling problem", she said.
She announced she would rule on the matter no earlier than next week.
A bill has already been passed in the US Senate allowing the families of the victims of the 11 September attacks to view the trial on closed-circuit television.
A similar arrangement was made for relatives of those killed in the Oklahoma bombing for the trial of Timothy McVeigh.
Zacarias Moussaoui faces six charges including conspiring to commit terrorism, to hijack and destroy planes, and to use weapons of mass destructions.
He could face the death penalty if convicted.
Last week, the court in Virginia entered a plea of not guilty for him, after he refused to enter a plea himself.
He is alleged to be the 20th hijacker, the man who should have joined the 19 others who seized control of four planes on 11 September and crashed them in New York, Washington and Pennsylvania, killing over 3,000 people.