The repeal means that the US has side-stepped huge World Trade Organisation (WTO) approved retaliatory tariffs of $1 billion from Canada and Mexico.

US Agriculture Secretary Tom Vilsack said: "The omnibus bill repealed the country of origin labelling (COOL) requirements for muscle cuts of beef and pork, and ground beef and pork. Effective immediately, USDA is not enforcing the COOL requirements for muscle cut and ground beef and pork outlined in the January 2009 and May 2013 final rules."

USDA will be amending the COOL regulations as expeditiously as possible to reflect the repeal of the beef and pork provisions.

Mr Vilsack's statement added that all imported and domestic meat will continue to be subject to rigorous inspections by USDA to ensure food safety.

The move was broadly welcomed by agricultural organisations.

North American Meat Institute President and CEO, Barry Carpenter, said: “We are enormously grateful that lawmakers have included language in the Omnibus bill to repeal mandatory country of origin labelling for certain meat products.

"Our elected leaders recognise the need for the United States to live up to its international trade obligations... This Congressional action is an important step in avoiding the financial harm so many industries will incur once Canada and Mexico initiate the tariffs sanctioned by the WTO’s ruling earlier this month."

The National Pork Producers Council (NPPC) President Dr Ron Prestage, also welcomed the move and added: “America’s pork producers are grateful that lawmakers, particularly Chairman Roberts and Chairman Conaway, recognised the economic harm we faced from retaliation because of the WTO-illegal COOL law.”

“I know tariffs on US pork would have been devastating to me and other pork producers.”

The Canadian Pork Council's Chair, Rick Bergmann, said: "Challenging the US COOL has been a long and expensive fight for Canadian producers. We look forward to the President signing the Bill to avoid retaliatory action and closing the book on this dispute."