New Zealand First leader Winston Peters is calling for a free trade agreement among Commonwealth countries, and wants to use New Zealand's CER agreement with Australia as a template.
He said a British exit from the EU could offer such an opportunity and could "heal a rift" with New Zealand that occurred when Britain became a member of European Economic Community in 1973.
Mr Peters also believes that New Zealand should take advantage of the troubles Russia is having with Europe and restore a full trading relationship with Russia.
Mr Peters' endorsement of CER as a model for others is a shift in position - at the 2014 election his policy was to review all bilateral free trade agreements, including the Closer Economic Relations agreement with Australia, to ensure they were in New Zealand's interest.
Speaking to an agricultural related industries conference in Auckland today, Mr Peters backed an exit by Britain ("Brexit") of the European Union - to be put to a referendum on June 23 - saying Norway had shown that Britain could flourish outside the EU.
Mr Peters noted that Conservative MP and London Mayor Boris Johnson supported an exit from the EU and had backed travel and work zones between Britain, New Zealand, Australia and Canada.
"Based on the highly successful Transtasman Travel Arrangement, it shows the opportunity that is within our grasp," Mr Peters said.
"While 'Brexit' is an opportunity for not just New Zealand businesses, product and people, it is an excellent opportunity to heal a rift dating back to 1973."
He said the pursuit of a free trade deal with Europe was "a fiction" because Europe still had farm subsidies.
"New Zealand First believes our oldest and most successful trade agreement with Australia, CER, provides the ideal template for Closer Commonwealth Economic Relations, or CCER.
He said it could become a model for a high quality future agreement not just with Britain but Canada, South Africa and India.
On the issue of Russia, Mr Peters said Prime Minister John Key had wrecked New Zealand's trading relationship with Russia in asking exporters to show constraint in solidarity with Europe.
A free trade deal negotiated with Russia by former Trade Minister Tim Groser was put on ice in the wake of Russia annexing Crimea and subsequent sanctions that followed.
Russia retaliated against sanctions by blocking food exports from Europe. The New Zealand Government asked major New Zealand dairy and beef exporters to show some solidarity with Europe by not taking advantage and replacing European suppliers.
Mr Peters said Europe's trade with New Zealand's markets, such as the United States, Korea, and China, had increased during the same period.
"New Zealand First is committed to rehabilitating the trade relationship with Russia that Mr Key went out of his way to wreck."