The Broadcasting Standards Authority has completed the first step in dealing with a complaint made by the Prime Minister against TV3.

Helen Clark and her press secretary, Mike Munro, have complained to the BSA over an interview by TV3's John Campbell.

The Prime Minister claimed she was "ambushed" over the genetic modification debate when Campbell asked her surprise questions last July based on claims in a book that alleged a government cover-up on the GM corn debate.

The authority issued an interim decision yesterday that it was entitled to accept the referral of a complaint made to TV3 by Helen Clark, which had been rejected by the channel. TV3 had claimed her referral to the authority raised new issues to the ones in her original complaint to them.

But the authority found the referral was an elaboration on the original and was not a "new" complaint.

Both parties have a month to appeal before the authority can make a further decision on an application of discovery made by Helen Clark.

She wants the BSA to order TV3 to deliver all written communication relating to the channel's access to the book and "confidentiality" surrounding its disclosure, and all video material relating to the preparation of the interview.

A final decision on the complaint is expected within a year.