"Because of our isolation, New Zealand's parliamentarians do not get enough opportunities to engage with important international organisations, particularly for opposition MPs," Mr Carter said in a statement.
"And this view was also shared by OECD deputy secretary-general Mari Kiviniemi and the director-general of UNESCO Irina Bokova."
Mr Carter said as well as honouring New Zealand soldiers who gave their life during conflicts including World War I, the delegation strongly advocated for New Zealand's economic interests, including seeking French support for a European Union-New Zealand trade agreement.
This lobbying took place at meetings with MPs from the French National Assembly and Senate, with the Speakers of both Houses, and with senior Government officials.
"Having elected representatives from the New Zealand Parliament at these occasions is important, not only to continue to recognise the sacrifices that were made by our soldiers, but also because of the significance of these commemorations to all French people," Mr Carter said.
On the trip is first-term Labour MP Adrian Rurawhe, Green Party foreign affairs spokesman Kennedy Graham, and first-term New Zealand First MP Fletcher Tabuteau and two parliamentary staff.
All the MPs except Mr Rurawhe have taken their partners on the trip.
MPs can downgrade from business class airfares and use the savings to help pay for their partners' travel, and any extra cost associated with partners must be met by the politicians.
The French leg of the tour wrapped-up on Friday night, and after a short flight from Paris to Dublin on Saturday the group had the weekend off except for a dinner hosted by New Zealand High Commissioner and former Speaker Sir Lockwood Smith.
Today they will tour Belfast and its Parliament Buildings.