Radio New Zealand Morning Report host Sean Plunket was "distressed" at being told to find another job if he didn't like his employer's decision he could not write a column for Metro magazine, he told the Employment Relations Authority.

Plunket took RNZ to the authority after he was refused permission to write the column, along with being refused permission to moderate two televised debates, for TVNZ and TVNZ6.

Plunket disagreed with RNZ's claim that the secondary work was a conflict of interest, saying his employer was not in competition with the other media, and the work would have helped raise his profile, and, in turn, RNZ's.

Plunket had previously done work for other media and moderated debates but had not informed RNZ because he did not see a conflict of interest in the roles.

At a meeting with RNZ's chief executive Peter Cavanagh earlier this year, Plunket was told he was part of the broadcaster's "brand", as though "anything I said or did anywhere would reflect on Radio New Zealand".

He said Mr Cavanagh later told him "you might find the offers stop coming if you don't have the profile of Morning Report" and "if you don't like it, get another job".

Plunket said he found Mr Cavanagh "menacing" and was distressed at the idea he may lose his job.

He received a letter at home by registered post telling him if he took up the Metro position, he would face disciplinary action.

Plunket said he believed he was being treated differently to other RNZ reporters and presenters, who were given permission to do similar secondary work.

RNZ journalists Chris Laidlaw, Kim Hill and Brent Edwards gave evidence this morning that they had done work for other media while employed by RNZ.

But RNZ said Hill and Laidlaw were entertainment presenters, whereas Plunket was a news presenter, so there were different ethical responsibilities in their roles.

Political editor Edwards had appeared on TVNZ's Agenda, but said he understood he was representing RNZ in that role and had not been paid.

RNZ's lawyer Michael Quigg said there were differences between Mr Cavanagh and Plunket's evidence of the meeting at which Plunket said he was threatened.

Mr Cavanagh was expected to give evidence later today.

The hearing is set down for two days.