The man tapped to head Mexico's finance ministry after Dec. 1 says officials are expected to sign a revamped trade agreement with the United States and Canada at the Group of 20 summit in Argentina this week.
Carlos Urzua said late Monday that "all possibilities" point to a signing in Argentina.
He said the pact would then have to be ratified by the legislatures in all three countries.
Urzua will lead the ministry when Mexican President-elect Andres Manuel Lopez Obrador takes office Saturday.
The new deal was once known as the North American Free Trade Agreement, but was renegotiated this year and been renamed the U.S.-Mexico-Canada Agreement, or USMCA.