Private litigant Graham McCready will ask a judge to require an Auckland cafe waitress to appear as a witness in court as part of his case against the Prime Minister.
Mr McCready is asking Auckland District Court for permission to prosecute John Key for assaulting Amanda Bailey when he pulled her hair.
Mr McCready said the Unite Union, which is representing Ms Bailey, had refused to co-operate with his prosecution.
But in a letter to Ms Bailey he said the prosecution would not be withdrawn in any circumstances.
In court documents Mr McCready also lists as witnesses the Prime Minister's wife Bronagh Key, Labour Party deputy leader Annette King, New Zealand First leader Winston Peters and TV3 reporter Tova O'Brien.
The documents say the hair-pulling has a sexual connotation.
The Prime Minister was on his way to Gallipoli for Anzac centenary commemorations when the story broke that he had to apologise for repeatedly tugging Ms Bailey's hair. The story instantly went global, with overseas news media mocking his behaviour.
Yesterday he told Radio New Zealand's Morning Report programme he sincerely regretted the hair-pulling incident and that "every person on the planet" would agree he had misread the situation.
Mr Key said he did not expect to face charges but had taken legal advice after Mr McCready made a complaint. He confirmed that he is paying for the legal advice he has sought.