Lord Hollick said in an interview with the Evening Standard today: "I think both Five and Channel 4 -- under Mark Thompson's leadership and now Andy Duncan's -- can see the considerable benefits of working together."
He said a merger would offer significant gains to both broadcasters.
"We have a lot of duplicated costs, we compete ferociously for bought-in material, we'd have the opportunity for cross-promotion."
Lord Hollick's line on United's 35% stake in Five is that it is "not for sale", yet he seems very intent on pushing a significant tie-up that would significantly increase Five's value.
Merger talks between Channel 4 and Five have been going on for a number of months although the idea of working together more closely dates back a number of years.
Current Channel 4 chief Duncan played down his interest in Five at last month's Edinburgh International Television Festival and media commentator Ray Snoddy recently wrote in Marketing that the idea was well and truly dead.
"It's time to hold a wake for a very bad idea -- the proposed merger of Five and Channel 4. Some people may wonder whether this is a bit premature for something that has not been officially declared dead. But even if there is still a slight flutter of a heartbeat, believe me, the idea is well and truly dead," Snoddy wrote.
Lord Hollick, 59, announced his plans to retire last week and United is searching for a replacement and is looking at internal and external candidates.
As well as its stake in Five, United owns business magazines and research firm NOP.
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