A proposed Pacific trade region may capture an additional $3 trillion in economic output after Canada and Mexico were invited to take part in talks with nine other nations.

A final deal that includes Canada and Mexico would create the U.S.’s largest trade accord, linking its North American Free Trade Agreement partners with eight Pacific-region nations. The negotiations would cover trading among economies with an estimated $20.5 trillion in output, up from $17.6 trillion among the nine partners, according to the Canadian statement.

More in Business Week