Mexican President Claudia Sheinbaum on Tuesday said Mexico will take action if an agreement with Washington regarding new tariffs is not reached by the August 1 deadline set by her U.S. counterpart Donald Trump.

The US is imposing a 17% tariff on most tomatoes imported from Mexico with immediate effect, the government said. The duty came into force after the US withdrew from a long-standing agreement with its southern neighbour, arguing that the deal "had failed to protect US tomato growers from unfairly priced Mexican imports".

President Donald Trump posted letters to the leaders of Mexico and the European Union, saying they had not done enough to head off the new tariffs.

America’s biggest trading partners have tried tactics ranging from appeasement to retaliation to avoid higher tariffs. All find themselves faced with similar threats from Washington.

U.S. stock indexes are edging mostly lower following President Donald Trump’s latest updates to his tariffs, but Wall Street is hanging near its record amid speculation about whether the president may ultimately back down.

US stocks are little changed as investors shrug off more tariff threats from Trump. Investors await inflation data and earnings for direction.

He told NBC News last week that he was considering hiking his current baseline of 10% tariffs on all non-exempted imports to 15% or 20%. And he has floated a 50% tariff on copper.