Mexico, the world's 13th-biggest economy, has accepted an invitation to join regional trade negotiations including New Zealand and Australia in a deal that could free up market access hindered by the 1994 North American Free Trade Agreement.
Mexican President Felipe Calderon and United States President Barack Obama told reporters at the Group of 20 leaders' summit that Mexico would join the nine countries holding Trans Pacific Partnership talks after signalling its desire to join last November.
Australia, Brunei, Chile, Malaysia, New Zealand, Peru, Singapore, the US and Vietnam hope to create a free-trade bloc spanning the Asia-Pacific region that extends into aligning regulatory settings and removing tariffs and quotas.
The addition of Mexico means New Zealand may be able to eliminate trade barriers originating from Nafta.
New Zealand exports to Mexico have been worth $116.2 million this year and totalled $414 million last year.
"The current TPP members particularly welcomed Mexico's commitment to achieving the shared goal of a comprehensive, high-ambition, next-generation agreement as rapidly as possible, consistent with the statements made by TPP leaders and trade ministers on November 12, 2011, in Honolulu," New Zealand Trade Minister Tim Groser said.
The TPP negotiations, which grew from New Zealand's P4 deal with Chile, Brunei and Singapore, have been widely opposed by anti-globalisation activists and academics over intellectual property demands made by the US and provisions that would let companies sue governments if policy decisions erode their profits.
Obama said Mexico and the US recognised growth was taking place in the Asia Pacific region and they needed to be part of that network of nations.
"To be able to create a high-standard trade agreement that further increases job opportunities, commercial opportunities, investment opportunities, I think will benefit citizens in both our countries," he said.
In a submission on opening up TPP negotiations to Mexico, Japan and Canada, Business New Zealand said letting Mexico join the TPP negotiations "offers considerable opportunity for New Zealand exporters" by restoring access to a market that cut out a number of local companies after the introduction of Nafta.
In putting its case to New Zealand, Mexican trade official Rosaura Castaneda Ramirez said the central American nation's growth prospects made it an attractive addition to the negotiations.
"TPP is a renewed opportunity to institutionalise the important bilateral economic relationship between Mexico and New Zealand."