National MP and former government minister Richard Worth on Thursday defended himself over allegations of a "sexual nature" levelled against him.
The National Party MP abruptly announced his resignation as a minister on Wednesday.
Police Minister Judith Collins on Thursday confirmed a criminal complaint has been laid against the former Internal Affairs Minister.
Ms Collins says she was contacted by Police Commissioner Howard Broad on Tuesday and was informed of an investigation into one of her colleagues that was of a "sexual nature".
There are separate allegations that Dr Worth displayed inappropriate sexual behaviour to a woman who is a member of the Labour Party.
On Thursday afternoon, Dr Worth released a statement defending himself over the allegations, saying the public should suspend any judgement until allegations against him have been resolved.
Dr Worth says he has not committed any offence and will defend himself "vigorously".
Police have confirmed the criminal complaint was laid in Auckland two weeks ago but has since been transferred to the Wellington criminal branch for investigation.
Radio New Zealand's political staff say it is understood the complainant is a Korean woman.
Dr Worth has close ties with the Korean community, including having held the position of chairman of the Korea New Zealand Business Council.
Prime Minister John Key on Thursday said he had phoned Dr Worth and encouraged him to come forward and speak publicly.
PM's handling of allegations under fire
The Labour Party on Thursday questioned Mr Key's handling of the criminal allegation, saying he received information about Dr Worth on 26 May and the matter could have been dealt with more promptly.
Mr Key on Wednesday defended the speed with which he has dealt with that claim, saying he acted as fast as he could, under the circumstances.
On Thursday, Mr Key was forced to also defend the thoroughness of an investigation conducted into a separate allegation of inappropriate sexual behaviour by Dr Worth toward a woman who is a member of the Labour Party.
Mr Key says his office investigated thoroughly the earlier claim of inappropriate sexual conduct brought to his attention by Labour, but was hampered by a lack of hard evidence.
But Labour says e-mail evidence was available and could have been requested at any time.
Mr Key says he accepted Dr Worth's denial of any wrongdoing when he was questioned about the claim.
While Mr Key's office did not seek to talk to the woman during its investigation into her claims, the Prime Minister has now said he would consider meeting her.
The woman says she is happy to do that and to provide copies of the messages.
Woman's statement tabled in Parliament
On Thursday night, Mr Goff tabled a statement in Parliament from the woman who made the allegation of inappropriate sexual behaviour.
Mr Goff says the Prime Minister has taken Dr Worth's word over the complainant, which is why he has gone public.
In the statement, the married woman says Dr Worth offered her two jobs and soon afterwards began calling and sending her texts which she says left her uncomfortable, saying they were "vulgar and sexually explicit".
They included references to her buying a transparent garment and suggestions they go swimming together.
The woman said some of Dr Worth's texts end with "xxx" and she had to ask her husband what this meant.
She says Dr Worth asked her to pray that something would happen to her husband so they could be together.
"I showed respect to Dr Worth as an older person and as a Minister of the Crown, but I repeatedly made it clear to him that I didn't want a relationship with him."
The woman said that, during the period 26 November 2008 to 23 February 2009, she received "approximately 40 text messages and more than 60 phone calls" from Dr Worth.
"I do not think that text messages and phone calls made by Dr Worth to me were acceptable. They were unwarranted. They left me feeling uncomfortable.
"I went to Mr Goff earlier this year because I wanted the contact from Dr Worth to stop."
The name of the woman has not been made public for privacy reasons.
