Sussex County in the U.S. state of Delaware is the country’s biggest producer of meat chicken, and the future of this business is largely dependent on overseas markets, especially for the dark meat that is less in favor in the U.S. than abroad, the NYTimes reports.

But one of the industry’s potentially most lucrative importers, South Africa, has been placing tariffs on American chickens since 2000, essentially shutting them out to protect its own chicken industry. This frustrates U.S. farmers, trade officials and members of Congress from the unfortunately named Chicken Caucus, according to NYTimes.

American officials are now threatening South Africa’s continued inclusion in AGOA, the African Growth and Opportunity Act trade partnership that has been particularly beneficial for South Africa. The charge is led by Senator Chris Coons, Democrat of Delaware, and Senator Johnny Isakson, Republican of Georgia — a huge chicken-producing state.

If South Africa continues to tax the chickens of America to protect its own, officials say, perhaps South Africa should be removed from the trade agreement that allows it to send its luxury cars, wines and other goods to the U.S.

“You want unlimited access to American market to sell autos, yet you won’t let my state send its biggest agriculture export into your country?” said Coons, who has been involved in African affairs for a while, according to NYTimes.

For some lawmakers the rejection of American chicken is emblematic of other problems and evidence that trade agreements often do not live up to their promises for the U.S. The dispute over chickens comes just as President Barack Obama is pushing an aggressive trade agenda in Congress.

“Members of Congress are fed up with this,” said Representative Rosa DeLauro, Democrat of Connecticut.

Passed in 2000, AGOA was intended to help bring impoverished areas of sub-Saharan Africa into the international economy duty free. South Africa — which accounts for the majority of U.S. imports under the AGOA trade deal and which exports billions of dollars in goods to America — began to impose large duties on chickens in 2000. U.S. officials believe it’s a trade violation. South Africa says the U.S. is trying to dump chicken on its market at below the cost of production.

The need to include South Africa in AGOA has been questioned for years, NYTimes reports. With its booming middle class, South Africa is a member of the Group of 20 largest industrial economies.

Chicken producers have been pressuring the White House on the issue, and lawmakers are considering dropping South Africa from the AGOA trade deal, set to expire in 2015 unless it’s extended. Isakson, Coons and others have met with South African trade officials, NYTimes reports.