There's no love lost between MediaWorks' radio and television news divisions, but after a bizarre stunt pulled on air by RadioLive host Sean Plunket against TV3's political editor Patrick Gower on Friday, the friction and fallout has been damaging.

Yesterday, Plunket was forced to read out a prepared statement on air apologising to Gower. But insiders say it's unlikely to be the end of the matter.

It all began when Plunket ambushed Gower on Friday about a comment he'd allegedly made on close friend Duncan Garner's RadioLive show following the Oravida scandal.

Plunket asserted Paddy had said there would be a bombshell before the election, suggesting he had prior knowledge of Nicky Hager's book.

Suddenly Gower was on trial. Plunket pumped him like a Guantanomo detainee, without the waterboarding.

Plunket went on the attack; Gower went on the defensive. And the listener was left confused and befuddled.

News boss Mark Jennings was furious. Why was the network's political editor being interrogated about his credibility by a broadcaster from the company's radio arm?

"Sean totally blindsided Paddy," said a MediaWorks source, "and that sort of behaviour has to stop. We need to play together as a company."

The audio has been pulled from the RadioLive website. Neither Plunket nor Gower would comment to The Diary, and a rep for the company said "there's nothing more to add to Sean's comments".

Plunket took to his show yesterday to read out an approved apology.

"On Friday I suggested Patrick knew about the Nicky Hager book in advance, and in partiular the material relating to Judith Collins," Plunket said contritely.

"Patrick was tricked into coming on air under false pretences. I then questioned him about this live on air without having any evidence whatsoever to support that claim.

"The claims were based on comments from listeners that I didn't check, and that I've since discovered, there is no basis for the claims.

"I apologise for any comments that I made that have undermined Patrick's professional reputation. Patrick's a respected political editor and a regular commentator on RadioLive who didn't deserve that treatment."

MediaWorks will be hoping this the end of the matter. It's radio survey time; this is not good publicity.