Imposing stiff tariffs on China and Mexico, as Republican presidential nominee Donald Trump has proposed, could push the U.S. into recession and cost 5 million U.S. jobs, according to a study by the Peterson Institute for International Economics.

The Peterson Institute, a Washington DC think-tanks that favors free trade, ran three computer simulations of the economic impact of placing 45% tariffs on Chinese goods and 35% tariffs on Mexico's. Under the most dire outcome, China and Mexico would retaliate with tariffs on U.S. goods and services, U.S. exports and imports would shrink, import prices would rise, stock prices would tumble and investment would plunge, resulting in recession within three years.