The Comprehensive and Progressive Trans-Pacific Partnership is open to all economies which accept its principles, signatory countries have agreed at their first commission meeting in Tokyo.

"Amid growing concerns over recent trends toward protectionism, Ministers shared the view that it is of paramount importance to maintain and further strengthen the principles of an effective, open, inclusive and rules-based trading system," a joint ministerial statement said.

"Ministers reiterated that the agreement is open to all economies which accept these principles and are willing to meet the high standards of the agreement and confirmed their strong determination to expand the agreement through the accession of those new economies."

Ministers also reaffirmed the importance of maintaining strong solidarity in "vigorously promoting free trade and economic integration in the Asia-Pacific region and beyond".

Trade Minister David Parker, who is in Tokyo for the meeting of 11 signatory countries of the Comprehensive and Progressive Trans-Pacific Partnership (CPTPP), welcomed the agreement on accession procedures.

"It was very pleasing to see CPTPP come to fruition with its entry-into-force at the end of December. I welcome the idea that those willing to meet CPTPP's high standards and objectives are now able to join the agreement over time," Parker said in a statement.

While he did not expect any formal applications soon, he looked forward to continuing discussions with interested economies on the basis of the agreed guidelines.

"In the meantime, I look forward to seeing the remaining signatories complete their domestic processes and join the seven who have ratified the agreement to date."

The agreement has been ratified by seven of the 11 CPTPP countries – New Zealand, Australia, Canada, Japan, Mexico, Singapore and Vietnam.

Brunei, Chile, Malaysia and Peru are yet to do so.

At the meeting, it was also agreed that New Zealand would host the next set of CPTPP meetings later this year.

No date had yet been set but Parker expected it to be in the second half of the year.

"This will be an opportunity to build on our collective commitment to ensure full and effective implementation of the agreement and to promote its expansion over time," he said.

The CPTPP was ratified by New Zealand in October and came into force on December 30 last year.

The Government has said it will open access for New Zealand exporters to 480 million consumers across 11 countries, including four which New Zealand had no trade agreement with.