Trade Minister Tim Groser has been reprimanded by the Prime Minister's chief of staff for excessive drinking on a return flight from government business overseas.
A spokesperson for Prime Minister John Key says Mr Key found out about the incident through an email from someone who had spoken to another passenger on the flight.
The spokesperson confirms that Mr Groser has been spoken to by the Prime Minister's chief of staff, Wayne Eagleson.
Mr Key won't comment further, and Mr Groser is overseas and can't be contacted.
