of tariffs the United States imposes on imports from those foreign countries. (6) Under the current negotiating process, negotiations to reduce or eliminate tariff barriers and nontariff barriers are separate and self-contained, meaning that tradeoffs are tariff-for-tariff and nontariff-for-nontariff. As a result, a tariff can be reduced or eliminated without securing elimination of the real barrier or barriers that deny United States businesses access to a foreign market. (b) Purpose The purpose of this Act is to require that United States trade negotiations achieve measurable results for United States businesses by ensuring that trade agreements result in expanded market access for United States exports and not solely the elimination of tariffs on goods imported into the United States. 3. Limitation on authority to reduce or eliminate rates of duty pursuant to certain trade agreements (a) Limitation Notwithstanding any other provision of law, on or after the date of the enactment of this Act, the President may not agree to a modification of an existing duty that would reduce or eliminate the bound or applied rate of such duty on any product in order to carry out a trade agreement entered into between the United States and a foreign country until the President transmits to Congress a certification described in subsection (b). (b) Certification A certification referred to in subsection (a) is a certification by the President that— (1) the United States has obtained the reduction or elimination of tariff and nontariff barriers and policies and practices of the government of a foreign country described in subsection (a) with respect to United States exports of any product identified by United States domestic producers as having the same physical characteristics and uses as the product for which a modification of an existing duty is sought by the President as described in subsection (a)