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.