The Lib Dems Deputy Leader Simon Hughes told ITV1's The Agenda that he is opposed to the statutory regulation of the press.
He told ITV News Political Editor Tom Bradby: "There must be a strong argument for making sure we don't have a dominant force which runs all the channels so we don't have the choice, they influence too much and set the prices, set the agenda."
"There is the other issue which is about regulation... I'm not for having a statutory system but I am for having a system that says look there will be a fall-back."
Lord Justice Leveson's report is published on Thursday.
The Agenda is on ITV1 at 10.35pm and at 11:35pm in Scotland.
Deputy Liberal Democrat leader Simon Hughes has admitted exchanging text messages with Labour's Ed Miliband. Mr Hughes said it was a sign of "sensible, grown up politics" to talk to politicians from other parties.
His comments come after Business Secretary Vince Cable said he had sent texts to Labour leader Mr Miliband and shadow chancellor Ed Balls said he could work with the Lib Dem Cabinet minister on measures to boost the economy.
Mr Hughes said: "I've had text messages with Ed Miliband, I have his number on my phone. "In sensible, grown up politics you talk to people about how you get the best deal for Britain.
"I have talked to Tories and Labour people all my life in to Parliament...working together is a very good thing."
Asked about the OBE that Gary Barlow is due to receive, Liberal Democrat deputy leader Simon Hughes told ITV News that his tax affairs "should be a relevant consideration" but "it's probably hard to undo an award that has already been announced."
"If you don’t pay your taxes you’re not a fully decent citizen," he said, adding that the honours committee "should make sure that people are clean as far as their tax affairs are concerned."