He added: “It’s a genuine free trade area.
“It doesn’t have its own parliament or court, it doesn’t impose laws upon its members, and it is focused on opening markets, not harmonizing and integrating.”
Britain has been looking to build global trade ties following its departure from the EU, and began negotiations in June two years ago to join the CPTPP.
Existing members of the group include Australia, Brunei, Chile, Japan, Malaysia, Mexico, New Zealand, Peru, Singapore, Vietnam and Canada.