From the Washington Post:
The leftist government of Ecuador, under pressure from the Obama administration for considering a request for sanctuary from the American intelligence leaker Edward Snowden, announced Thursday that it will back out of a preferential trade pact with the United States that top Ecuadoran officials say is being used to blackmail their country.
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The Andean Trade Promotion and Drug Eradication Act has allowed Ecuadoran exporters of flowers, tuna, artichokes and many other products to ship tariff-free to the United States.
“The preferences were authorized for Andean countries as compensation for the fight against drugs but soon became a new instrument of pressure,” Alvarado said.
The pact was designed to help generate jobs in countries involved in the drug trade; although Ecuador does not produce cocaine, it is an important drug conduit and is vulnerable to organized crime groups because of its weak institutions, according to State Department counternarcotics officials.
It seems that those statements relate to the Andean drug measure preferences, not to GSP (according to Inside U.S. Trade). A review of Ecuador's eligibility for GSP benefits is ongoing (and also involves consideration of the enforcement of investment arbitration awards).
Here's what I'm wondering. Challenges to GSP exclusions are difficult, because if you want to get those preferences eventually, it may be best to avoid aggravating the country granting them. But let's say Ecuador were to give up on all U.S. preferences, including GSP. Would it then be willing to bring a WTO challenge to the conditions often imposed on GSP beneficiaries? A related question: If it renounces all benefits, can it claim any nullification or impairment?