WASHINGTON — House Republicans are hoping to repeal a law requiring country-of-origin labels on packages of meat to avoid costly trade retaliation from Canada and Mexico.

The World Trade Organization ruled against the law last month, saying the labels that say where animals were born, raised and slaughtered are discriminatory toward the two U.S. border countries. Canada and Mexico have said they will now ask the WTO for permission to impose billions of dollars in tariffs on U.S. goods.

The House on Wednesday began debate on legislation that would repeal the law for beef, pork and poultry.

The labels tell consumers what countries the meat is from: for example, “born in Canada, raised and slaughtered in the United States” or “born, raised and slaughtered in the United States.”

The WTO ruled against the labels last year and then denied a U.S. appeal last month. The Obama administration has already revised the labels once to try to comply with previous WTO rulings. Agriculture Secretary Tom Vilsack has said it’s now up to Congress to change the law to avoid retaliation from the two neighbor countries.

The law was initially written at the behest of northern U.S. ranchers who compete with the Canadian cattle industry. It also was backed by consumer advocates who say it helps shoppers know where their food comes from. Supporters have called on the U.S. government to negotiate with Canada and Mexico to find labels acceptable to all countries.

Rep. Marcy Kaptur, D-Ohio, said repeal would be premature, adding: “Our people deserve a right to know where their food is produced and where it comes from.”

Many in the U.S. meat industry – including processors who buy animals from abroad – have called for a repeal of the law, which they have fought for years, including unsuccessfully in federal court.

Canada and Mexico have opposed the law because it causes their animals to be segregated from those of U.S. origin – a costly process that has forced some U.S. companies to stop buying exports.

Congress required the labels in 2002 and 2008 farm laws. The original labels were less specific, saying “product of U.S.”