Trade Minister Tim Groser spent almost $250,000 on international travel in the first quarter of this year.
Mr Groser is on the short-list for the top job at the World Trade Organisation and has spent much of this year overseas trying to garner support for his bid.
He is by far the biggest ministerial spender in the year to the end of March, with $248,838 spent on international trips.
Not surprisingly Foreign Affairs Minister Murray McCully was next with $99,872.
Prime Minister John Key spent $34,857, while his deputy Bill English spent $26,583.
Mana Party leader Hone Harawira spent $31,809 on his total expenses, which includes travel and accommodation. He was the highest spending non-minister.