Five other countries interested in joining TPP

The 12 signatories have two years to ratify the deal which requires six to do so in order for it to proceed, including the US and Japan.

Five other countries have informally expressed interest in joining the Trans Pacific Partnership agreement once it has been ratified by the original 12 signatories, according to chief negotiator David Walker.

To date TPP is confined to New Zealand, Australia, the US, Canada, Mexico, Japan, Singapore, Malaysia, Vietnam, Chile, Peru, and Brunei. Walker said Korea, Indonesia, China, the Philippines and Thailand were studying details of the recently-hammered out deal, which was more than seven years in the making, to see if they wanted to take that informal interest further, but "at the moment they can't join because the agreement doesn't exist."

When asked how many he thought would take it further, Walker reverted to 'no comment'.

The 12 signatories have two years to ratify the deal which requires six to do so in order for it to proceed, including the US and Japan.

Around 200 people turned up in Auckland today for the first of 16 government roadshows and hui outlining details of the TPP, with fewer than a dozen protesters waving placards outside the venue, including one that said "Kiwis strike back".

Four people dressed as clowns had evaded the tight security to access the venue and were eventually ousted after trying to disrupt the speakers by laughly loudly and letting off balloons.

In response to a question from an Auckland pharmaceuticals and toiletries exporter which is trying to establish new markets in Indonesia and Korea, Walker said TPP was a "living agreement" in two ways. The provisions could continue to evolve as economies grow and the partners wanted to do new things together, and it was also possible for new members to be added, he said.

Adding new members came under discussion during the signing ceremony of the agreement in Auckland last month on the need for a formal process to add others over the next few years.

There's been interest from the start in encouraging more and more of the major trading partners in the Asia Pacific region, and Indonesia and Korea are included in that.

"There's been interest from the start in encouraging more and more of the major trading partners in the Asia Pacific region, and Indonesia and Korea are included in that," Walker said. "But right now all 12 countries are focused on getting the agreement ratified in their domestic markets."

The existing agreement, which is New Zealand's largest ever trade deal, already covers 36 percent of the world's gross domestic product and 40 percent of New Zealand's exports.

Late last year US president Barack Obama urged more Southeast Asian nations to join the deal, saying those that are highly dependent on trade may stand to lose if they don't.

Similarly, Prime Minister John Key said last November that Apec no longer needed to look at developing a region-wide free trade agreement covering all 21 members when others could simply join the TPP instead.

China has followed the progress of TPP during the course of the negotiations and we have talked to them about that.

However, China's president Xi Jinping has been pushing for movement on a potential Free Trade Area of the Asia Pacific (FTAAP) deal. A strategy study on issues relating to FTAAP is due by the end of the year.

At today's roadshow Auckland mayoral hopeful Penny Bright questioned how TPP could be in New Zealand's best interests given it doesn't include our second biggest trading partner, China, and Obama had been quoted as saying "if we don't write the rules, then China will write the rules in the region".

Walker said the benefits - including an estimated additional $2.7 billion to New Zealand's GDP each year from 2030 - were outlined in an extensive government report on the details of the deal. Expected costs are estimated to be between $75 million to $80 million, mainly from extending copyright protection from 50 to 70 years.

He said it had been made clear throughout the lengthy TPP negotiations that it was "not an anti-China process".

"China has followed the progress of TPP during the course of the negotiations and we have talked to them about that," he said."China is studying it now with particular interest."