Police are investigating after a teenage woman complained of inappropriate behaviour following a Young National event.
The 17-year-old woman was a guest at the political youth wing's Christmas drinks at a central Auckland bar last Tuesday, Newsroom has reported.
Following the event, the woman and some friends reportedly went to a young man's nearby apartment .
There, the man allegedly grabbed the woman's face and tried to kiss and grope her. He then allegedly pursued the woman after she fled the apartment block.
The woman was a guest at the event and not a member of the Young Nats, Newsroom report.
Police have issued a statement, confirming they're investigating a complaint made on the night of 20 November in Auckland Central.
"Police are currently making enquiries and we are not in a position to provide further details at this stage," the statement said.
National leader Simon Bridges said he was informed of the complaint by his chief of staff on Friday and sought assurances that it had been handled appropriately.
"Actually things were done right, in terms of a health and safety plan, on a licensed premises, IDing, food, cash bar.
"And then ... upon learning about [the complaint], the party has taken all of the responsible and caring steps that should be taken."
The alleged incident was "regrettable" but had been dealt with "very responsibly", Mr Bridges said.
"It was made clear to the complainant what her options were and indeed she was encouraged to go to the police, which is what has happened."
Party president Peter Goodfellow said a member of the Youngs Nats contacted the party about the complaint, but did not tell him who either the man or woman involved were.
"We're offering a lot of support and a lot of advice to the intermediary who has come to us," Mr Goodfellow said.
"We don't know who either of the two people are. We can't very do much in relation to that."
At least two National MPs - Andrew Bayley and Simeon Brown - were at the earlier event.
"It was very, very quiet, subdued. Most us there were just thanking the Young Nats for what they were doing," Mr Bayley said.
Mr Brown said he attended the Christmas drinks "very briefly" and left the bar early.
The police investigation follows an earlier inquiry into allegations of sexual assault at a Young Labour camp in Waihi in February.
A 20-year-old man has since been charged with four counts of indecent assault.