The TPP, a trade deal between the US and 11 Pacific Rim nations, was agreed in principle on 6 October after negotiations lasting nearly five years. This will open up markets from Asian counties including Japan and Vietnam.
The seven former secretaries, from across the political spectrum, said the new markets for export were critical for farmers and rural communities.
In the letter, the former secretaries said they supported a vote of approval by Congress.
TPP 'important' for farmers
“We know from experience how important such agreements are to the economic well-being of our farmers and ranchers. In every negotiation where agriculture has been on the agenda these negotiations have expanded our markets, boosted farm incomes and, in the process, created new jobs, both on-farm and off-farm, in rural America,” the former secretaries said.
They claimed that TPP was a 21st-century agreement that set enforceable ‘rules of the road’ for trade throughout the region and said it should be an "open platform" for other countries to potentially join.
The former secretaries also highlighted the non-economic benefits as it will solidify a working relationship with countries that have "both foreign policy and national security implications".
The letter also concluded with: "For American agriculture there is no downside to TPP, and there is substantial upside. Hence, we strongly support a vote of approval by the US Congress."