Andrew Neil, the star presenter and chairman of GB News, is taking a break from the new channel less than a fortnight after it went on air for the first time.
The 72-year-old veteran broadcaster announced during his show on Thursday night that he would absent for the "next few weeks" as he admitted the network had endured a "rocky start".
Colin Brazier, a former Sky News presenter, will take over Mr Neil’s 8pm slot until he returned before the end of the summer.
Mr Neil, who is also chairman of the broadcaster, added: "Yes we had a bit of a rocky start at the launch of GB News. We are a start-up. They are always a bit rocky these start-ups, but we are up and running as you can see.
"We get better every day and there is clearly an appetite for what we are doing. In two short weeks we have already built a loyal audience, which has beaten all of our expectations.
"It is often bigger than the other news channels and it is growing."
It comes amid a turbulent launch for GB News, which has been hit with an advertising boycott, technical glitches and a row with the BBC over access to "pool" footage of public events.
GB News is trying to capitalise on the culture wars gripping the nation with a right-leaning stance which targets viewers that dislike the coverage offered by the BBC.
It launched with more than 250,000 viewers on Sunday June 13, trumping ratings by BBC News and Sky News.
The channel also attracted more than 350 viewer complaints over comments made about coronavirus by Tonight Live presenter Dan Wootton on Sunday night.
Mr Neil delivered a robust defence of GB News last week, branding political activists who tried to starve the network of advertising income as "far-Left agitators and cranks".
The campaign group Stop Funding Hate launched a public attack on GB News by using social media to pressure some of the world’s biggest brands to pull their advertising from the station.
Companies such as Moneysupermarket, Vodafone, Bosch and Ikea then sought to distance themselves from the boycott after initially pulling their ads. Several of the businesses said they could choose to resume media campaigns following a review.
Some brands indicated that they pulled adverts because they had not given permission for these to be included on GB News.
The channel’s advertising sales are handled by Sky Media, part of broadcaster Sky, which negotiates on behalf of its own channels as well as third parties such as Channel 5, Fox and MTV. It typically posts adverts on channels based on the expected age group and social demographic of their viewers.
- Read more: Boycotts, bust-ups and technical mayhem: the tumultuous first week for GB News