By Kevin Young
Entertainment reporter, BBC News
Channel 4's head of news has said her network has "never served the public better", following a demand from ITV's Charles Allen that it should "grow up".
Ms Byrne called presenter Jon Snow "the soul" of Channel 4
Dorothy Byrne claimed C4 screened more news and current affairs in primetime than any rival broadcaster, with news presenter Jon Snow at its "soul".
Outgoing chief executive Allen called for a "fundamental remodelling" of C4's remit at the Edinburgh TV Festival.
But Ms Byrne said "no other broadcaster has more serious programming".
Ms Byrne challenged Mr Allen during a panel session that assessed the impact of his keynote MacTaggart Lecture.
"I am really surprised that Charles Allen says he doesn't know where the soul of Channel 4 is," Ms Byrne told the BBC News website.
"The viewers know it lies inside Jon Snow every night, in the heart of primetime, presenting Channel 4 News."
Mr Allen "calls into question how we are servicing our public service remit and that does not chime with my experience", said Ms Byrne, who previously worked at ITV.
"At Channel 4, in news and current affairs, we have never served the public better.
"Forty hours, in primetime, of Dispatches every year. Twenty Unreported Worlds every year.
"We used to have only five hours of news [a week], now we have eight hours of news.
"No other broadcaster has more serious programming in the heart of primetime."
She advised Mr Allen to "watch Channel 4 now that you've got some time on your hands, because I think you'll get a different picture to the one you presented".
Mr Lygo said there was no end in sight for reality show Big Brother
Mr Allen rebutted her remarks on stage: "I do actually watch Channel 4 and I agree that the news is superb. [But] that only represents 5% of Channel 4's overall output."
Channel 4 programme controller Kevin Lygo said it was "slightly odd" that Mr Allen's speech on Friday mentioned "everyone else but ITV".
"In a way, that was systematic of maybe some of ITV's current worries," he said. "There wasn't a clear, big overview of ITV, which I thought he was going to do."
In a separate session, Mr Lygo insisted Channel 4 would always "deliver to our remit, or we would be told off by Ofcom".
If anything, his network "over-delivered", he said.
"Constantly, we at the channel are working and trying to figure out the best way of delivering the remit and giving people what they want to watch."
"I'm not going to talk about ITV [further]," he added. "I don't know anything about it. I never watch it."
Mr Lygo went on to praise C4's reality TV show Big Brother, calling it "the most extraordinary show that's come along, ever".
"When it's going well, it attracts so much attention. It's a fascinating thing that can be interpreted on so many different levels.
"It has become an established summer event, a bit like Wimbledon. I see no reason why, if we protect it, it can't keep coming back every summer forever."
The seventh series, which came to an end earlier this month, has faced criticism from psychologists over the selection of contestants.
It is also being investigated by a premium rate watchdog following 2,700 complaints about a telephone vote which reinstated an evicted contestant