"I consider attributing blame to any other person to be completely unjustified."
Mr Riches said Mr Gilmore tried to "use his status as a Member of Parliament to his own advantage once he had been denied further alcohol service" and "threatened to have the Prime Minister's Office intervene and end the waiter's employment".
Mr Riches confirmed Mr Gilmore asked the waiter "Don't you know who I am?" and gave him his business card to verify his identity, "which was extremely embarrassing".
"After Mr Gilmore departed I was left to explain to the staff member that the powers of a backbench list MP are rather limited, do not extend to the firing of restaurant staff and that his job was safe," Mr Riches said.
Mr Key yesterday said: "Any suggestion that a member of parliament sought to use the influence of the Prime Minister's office inappropriately is a serious matter.
"My chief of staff has rung Mr Gilmore this afternoon and Mr Gilmore refuted the allegation. Mr Gilmore indicated that he did not believe that he used the words claimed in Mr Riches' statement."
Through a spokeswoman, Mr Key said he had accepted Mr Gilmore's apology.
He was "not going to get into the detail of claims and counter-claims but expected that Mr Gilmore has learned a lesson from the whole thing". But if a staff member or the management at the hotel wanted to lay a complaint, "the Prime Minister's office will ensure the complaint is thoroughly investigated".
While being drunk and obnoxious in a restaurant is unlikely to result in serious disciplinary action, Mr Gilmore may be in trouble if Mr Riches' account is verified and shows Mr Gilmore misled Mr Key's office.
Mr Gilmore came into Parliament on the National Party list in the 2008 election but did not get back in 2011.
He returned to Parliament to fill the vacancy created when Speaker Lockwood Smith resigned to become High Commissioner to London.
His career has been marked by minor controversies including the falsification of qualifications listed on the biography supplied to and published by Parliamentary Service.
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