Fortunately for chocolate-lovers across the U.S., candy aisles are stocked and ready this Valentine’s Day thanks in no small part to the continued existence of the North American Free Trade Agreement.

America’s Nafta partners supplied more than three-quarters of U.S. chocolate imports last year, with Canada shipping more than $1.4 billion worth of treats and Mexico an additional $538 million, according to data from the Census Bureau.

Popular American candy makers The Hershey Co. and Mars Inc. have manufacturing plants in the three countries as they take advantage of low—and in most cases nonexistent—tariffs provided under the 24-year-old trade pact. Hershey imports 15 percent of its products from plants in Canada and Mexico for domestic consumption.

It should come as no surprise then that the Pennsylvania-based confectioner says a demise of the trade pact would disrupt supply chains, boosting export costs in the region by as much as 20 percent. That makes President Donald Trump’s repeated threats to withdraw from Nafta if current negotiations don’t go his way a potential problem for chocoholics and lovebirds throughout the U.S.