New York (CNN Business)Tariff Man has struck again.
US stock index futures and Asian stock markets, including shares of Japanese and South Korean automakers, tumbled Thursday after President Donald Trump said the United States will impose a 5% tariff on all Mexican imports.Japan’s Nikkei (N225) and South Korea’s KOSPI (KOSPI) fell about 1% during early morning trade on Friday. Dow futures, S&P 500 futures and Nasdaq futures were all down about 0.7% on Thursday evening.Mexico is one of America’s biggest trading partners and many US companies — including Ford (F) and Walmart (WMT) — rely on the country as a central part of their supply chains. Walmart declined to comment Thursday.Read MoreThe country is also a regional manufacturing hub for major Japanese and South Korean automakers that assemble and ship cars from Mexico to the United States. Shares in Mazda (MZDAF) and Kia dropped by more than 6%, while Toyota (TM), Honda (HMC), Nissan (NSANF) and Hyundai (HYMTF) fell around 3% or more. Trump tweeted that the tariffs on Mexico would take effect on June 10 and remain in place until “illegal migrants coming through Mexico, and into our Country, STOP.”Trump, who has called himself “Tariff Man,” warned that the tariff will increase until “the illegal immigration problem is remedied.”The White House indicated the tariff would increase to 10% on July 1 if Mexico does not comply. If the country continues to not act, the White House said, the tariff will increase to 15% on August 1, 20% on September 1 and 25% on October 1.Trump announces tariffs on Mexico starting June 10 if it doesn't slow flow of migrants“Tariffs will permanently remain at the 25 percent level unless and until Mexico substantially stops the illegal inflow of aliens coming through its territory,” the White House said.Overnight moves in stock futures can be amplified by lower trading volumes. The threat sent the Mexican peso plunging about 2% against the US dollar. The latest tariff threat comes at a delicate time in global financial markets.US stocks have slumped and bond yields have plunged due in part to worries about the escalating trade war between the United States and China. Investors fear the tit-for-tat tariffs — and threats of non-tariff retaliation — will slow economic growth, dent consumer confidence and derail business investment. Imposing tariffs on Mexico may only exacerbate those trade concerns.The US Chamber of Commerce has estimated that about 6 million US jobs depend on trade with Mexico.