One manufacturer told NBC News that she had managed to push the existing 45% duty on her products onto American customers.

With almost half of auto parts used in the manufacture of U.S.-owned automobiles coming from outside the country, the industry faces mounting costs of production and shrinking profit margins, while suppliers face competitive pressures to move production domestically.

Auto workers expressed uncertainty and hope outside a Stellantis assembly plant in central Mexico that is scheduled to begin a month-long pause in production