The exploratory talks were reported by The Business newspaper on Sunday. The paper said the talks brought together Channel 4 chief executive Mark Thompson and Lord Hollick, the chairman of United Business Media who owns 35% of Five. The majority shareholder in Five is RTL.
It had been known that Five and Channel 4 were interested in a possible tie-up on airtime sales with BSkyB seen as another partner, but the paper quotes an unnamed source as saying that the talks went further.
"They have indeed talked. Contrary to what is being admitted, the discussion ranged rather wider than the simple matter of airtime sales," the senior source said.
However, with Channel 4 being state owned it is unclear how far the talks could really go. The government has never given any indication that it plans to float the advertising-funded Channel 4.
The airtime sales talks were put into motion following fears about the creation of a single ITV sales house. Five and Channel 4 were concerned that alone they would come under pressure from the merger of Carlton and Granada's sales operations.
The merger has since happened but there has been no further movement by Five and C4 since the ITV consolidation was completed last month.
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