Sen. Chris Coons of Delaware has issued a strong warning to South Africa: Drop your “unfair” duties on U.S. poultry or prepare to see your trade benefits disappear.

Since 2000, the Republic of South Africa has subjected U.S. bone-in poultry to “anti-dumping” duties, penalties that countries impose on imports they believe are priced suspiciously low. The duties have effectively blocked U.S. poultry producers from a growing market, costing the industry millions.

South African officials say their policy is consistent with World Trade Organization legal requirements and that U.S. and South African industry and government officials are discussing possible solutions.

Coons, whose home-state’s top agriculture product is poultry, says the policy is not only unfair but illegal, based on a 2013 WTO ruling in favor of the United States in a similar dispute with China. He’s using the upcoming reauthorization of the African Growth and Opportunity Act as leverage to force a resolution.

“I will find a way to prevent South Africa from benefiting from AGOA if we cannot resolve their illegal ban on the importation of U.S. poultry,” Coons said in an interview.

The Senate Finance Committee is expected to soon take up reauthorization of AGOA, a 2000 law that allows sub-Saharan African countries working to improve their legal systems, human rights records and labor standards to have greater access to U.S. markets.

Coons and Republican Sen. Johnny Isakson of Georgia plan to urge Finance Committee Chairman Orrin Hatch of Utah to quickly take up the bill – and find a way to prevent South Africa from benefiting from AGOA as long as it continues to block U.S. poultry from its market.

Coons is the former chairman of the Senate Foreign Relations Subcommittee on Africa. Isakson serves on the Finance Committee.

“It’s not fair for them to continue to get that benefit when they aren’t playing fair with American exports,” Coons said.

South Africa benefits greatly from the law. Its exports under AGOA were valued at $3.6 billion in 2013, and 42 percent of the country’s exports to the United States, mainly manufactured goods, enter duty-free, according to Sidwell Medupe, spokesman for the country’s Department of Trade and Industry.

The department estimates AGOA generated about 350,000 direct jobs and 1.3 million indirect jobs in sub-Saharan Africa, while creating about 100,000 jobs in the United States.

South Africa is seeking renewal of AGOA for at least 15 years “without any new and onerous eligibility criteria,” Medupe said in a statement.

“This is crucial for Africa’s regional economic integration efforts,” he stated.

Opening the South African market is important for the U.S. poultry industry, especially after a Russian ban on U.S. food imports, said James Sumner, president of the USA Poultry and Egg Export Council. U.S. poultry exports had a 5-percent share of the South African market before the duties were imposed in 2000 and the industry expects that “fair access” to the market would lead to about $120 million in sales, he said.

“It makes no sense for the United States to give special preferences to countries that treat our trade unfairly,” he said.

Mike Little, director of export sales at Mountaire Farms in Millsboro, Del., said Delaware growers stand to gain from opening up South Africa.

“The more places we have to sell our chicken, the better the industry will be,” he said. “It’s a trickle-down effect.”