The issue focused on the six other countries in the six-country free trade area, all of which are also signatories to the trade deal.

U.S. President Donald Trump's administration is looking to fast-track the deal, as he has made it a top priority.

The 14-member trade deal, which was signed in 2015, was seen as a major step forward in what was then a rather poor state of relations between the U.S. and other members of the World Trade