It looks like Maori Party MP Hone Harawira will have to pay back some of the taxpayers' money he received after he decided to take a holiday in Paris with his wife instead of attending a parliamentary conference.
Labour deputy leader Annette King said Mr Harawira's actions showed why the public wondered about MPs' perks.
Speaker Lockwood Smith said Mr Harawira may be asked to pay back some travel costs after leaving a conference in Brussels to see the sights in Paris.
"How many times in my lifetime am I going to get to Europe? So I thought, 'F*** it, I'm off. I'm off to Paris'," he said.
Mr Harawira, whose wife Hilda accompanied him on the trip, paid for the extra travel himself.
He said issues to be discussed at the meeting had been covered at a dinner the night before.
European Parliament MP Mara Bizzotto - who chaired the delegation for relations with Australia and New Zealand - "was cool with it", he said.
Ms King asked why Mr Harawira bothered to go to the dinner for the discussions if he had not intended to go to the meeting.
"I understand why he'd want to go to Paris, but perhaps he could have done that when the conference finished, rather than leave a conference that taxpayers are paying for and head off with his wife to have some sightseeing," she said.
"I think that really does make people wonder about parliamentary travel and taxpayers' money."
Mr Harawira was unrepentant about the trip and didn't believe he should have to pay back the money given that he had covered the issues being discussed at the conference and later followed them up.
Dr Smith did not agree, saying that his approval for inter-parliamentary travel carried an expectation that delegations would adhere to the official programme.
"I would expect a recovery of some of the costs if a delegate on an official inter-parliamentary visit takes an unscheduled day's leave for private purposes."
Mr Harawira accepted the trip to Paris was "outside the boundaries, but I don't feel uncomfortable with it".
He was glad he had undertaken the side trip, saying it would have been "dumb" not to visit such a wonderful city.
The other two MPs in the delegation, National MP Katrina Shanks and Labour MP Rajen Prasad, attended the meeting, which discussed relations between the EU and New Zealand, family and youth policies and multiculturalism.
In 2007 Mr Harawira was told to pay back some flights after he left mid-way through a four-day select committee trip to Melbourne, so he could visit Aboriginal groups in Alice Springs.
Ms King said Mr Harawira's second "walkabout" should give him food for thought.
"I would just hope that when people are chosen to go on a trip to represent New Zealand at taxpayer expense that they actually do what is required of them, and bring back the ideas and the contacts with them."
Mr Harawira said he had received no negative reaction from his constituents.
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