WASHINGTON, May 20, 2015 – Farm groups and agribusiness companies are urging the Senate to reject a proposed amendment to the fast-track trade bill aimed at stopping countries from manipulating their currency.

A letter sent to senators said the amendment proposed by Rob Portman, R-Ohio, and Debbie Stabenow, D-Mich., “would most likely kill” the Trans-Pacific Partnership negotiations.

The signers of the letter include the American Farm Bureau Federation, Cargill Inc., Smithfield Foods, American Soybean Association, National Corn Growers Association, National Milk Producers Federation, National Pork Producers Council, Pet Food Institute and Western Growers Association.

Supporters of the Trade Promotion Authority legislation have considered the currency amendment one of the biggest threats the bill faces.

Senate Majority Leader Mitch McConnell, R-Ken., said Tuesday the amendment would lead to a presidential veto and is opposed by most Republicans. “We’d like to send a bill to the House that’s in a form that they can live with,” McConnell said.

The amendment would make it a principle negotiating objective to include enforceable provisions in trade agreements to prevent currency manipulation. Stabenow argued that currency manipulation is the “No. 1 trade-distorting policy in the world” and poked fun at arguments that the amendment is unnecessary because Japan isn't manipulating its currency. “If they don’t do it anymore, then why in the world  would they walk away from a negotiation, if we have a negotiating objective on currency?" she asked.

McConnell said he is intent on passing the bill (HR 1314) this week ahead of the Memorial Day recess even as he tried to reach an agreement to limit the number of amendments that would receive votes. He filed cloture on the legislation Tuesday evening, which would allow for a vote to end debate on the bill as early as Thursday morning.

The bill would set negotiating guidelines for trade deals and ensure that they get an up-or-down vote in the House and Senate without threat of amendment.