Last month, it was reported that Karmazin, along with other US TV executives, had travelled to London to talk to Granada and Carlton Communications, the ITV companies, after the draft communications bill cleared the way for companies outside the EU to take controlling stakes in ITV.
Speaking at a conference in Boston, sponsored by US cable TV organisation the Cable & Telecommunications Association for Marketing, Karmazin admitted that a takeover of either ITV company looked unlikely at the moment.
He said: "The stocks of all the publicly traded media companies in the UK are trading at multiples higher than here in the US."
Karmazin made the point that there would be a number of benefits to buying into ITV, although its price would hold him back.
He said: "Core competency? Yeah. Could we grow it? Probably. Right price? Not looking like it today."
However, he did say that Viacom may still keep its options open for a while to see what happens when the communications bill is implemented next summer.
He said: "It won't happen for another year, so we'll see."
His comments nudged Carlton's share price down 1% to 175p at lunchtime, although Granada's shares edged up 0.5% to 97.75p
Bob Wright, chairman and chief executive of General Electric-owned broadcaster NBC, was also reported to have travelled to London last month to look at potential acquisitions, although its position on the price of the ITV companies is unclear.
AOL Time Warner has already ruled itself out as a potential suitor to Carlton or Granada. Last month, chief financial officer Wayne Pace said: "We're not in a position of doing anything right now in the acquisition area."
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