The invitation to join the club of now 11 Pacific nations was first announced in July, but all governments needed to ratify the inclusion.
The U.S. completed its 90-day Congressional consultation on Monday, the last hurdle in the process.
Canada, along with Mexico, has come late to talks that are already well underway, and will likely be expected to adopt decisions already reached by the other members — Australia, Brunei, Chile, Malaysia, New Zealand, Peru, Singapore, the United States and Vietnam.
While that has raised issues among critics, trade lawyer Lawrence Herman of Cassels Brock says the situation is not as severe as some suppose.
"As a practical matter, Canada would probably have to accept any deals already done," he said.
"But the TPP has a long, long way to go and once Canada gets into the game in December we’ll have as much influence as any of the others in the remaining issues ... and there are many still on the table."
The talks, like other trade negotiations, have been conducted behind closed doors, although some of the sensitive issues for Canada will seem familiar to free trade watchers, including intellectual property and Canada's protectionist agricultural practices.
Trade Minister Ed Fast, who is travelling in the Middle East this week, said in a news release issued in Ottawa that joining the TPP would be good for the economy.
"Opening new markets and increasing Canadian exports to fast-growing markets throughout the Asia-Pacific region is a key part of our government’s plan to create jobs, growth and long-term prosperity," he said.
The government is currently pursuing a host of big trade agreements, including free trade arrangements with the European Union, Japan and India.
The TPP market encompasses more than 658 million people and has a combined gross domestic product of about $20.5 trillion, larger than that of the U.S. and Europe.
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