Donald Trump smiles while speaking during a Presidential Medal of Freedom ceremony for former NBA basketball player and coach Bob Cousy of the Boston Celtics in the Oval Office

Donald Trump has launched an extraordinary attack on the Federal Reserve and its chairman Jerome Powell while seemingly demanding US companies cease trading with China “immediately” as the rival superpower upped the ante in their ongoing trade war by hiking tariffs on $75bn (£61bn) of American goods.

After Mr Powell addressed a central bank symposium in Wyoming and declined to say he would cut interest rates in accordance with the president’s wishes, the commander-in-chief exploded on Twitter and asked who is the “the bigger enemy” of the US, Mr Powell or Chinese premier Xi Jinping.

“Our Country has lost, stupidly, Trillions of Dollars with China over many years,” he ranted, ordering American businesses to seek alternatives to working with China and telling US delivery companies like FedEx and UPS to “SEARCH FOR & REFUSE all deliveries of Fentanyl from China”, blaming Beijing for the US opioid crisis.

Stocks fell sharply on Wall Street after Mr Trump said he would respond to China’s latest tariff increase and called on US companies to consider alternatives to doing business in China.

The Dow Jones Industrial Average sank more than 300 points after the president made the announcements on Twitter.

Trump protests: President visits Texas and Ohio after mass shootings Show all 31 1 /31 Trump protests: President visits Texas and Ohio after mass shootings Trump protests: President visits Texas and Ohio after mass shootings Miami Valley Hospital, Dayton Demonstrators chant as they protest the arrival of President Donald Trump outside Miami Valley Hospital after a mass shooting that occurred in the Oregon District AP Trump protests: President visits Texas and Ohio after mass shootings El Paso Trump headed to El Paso, after visiting Dayton, Ohio to offer a message of healing and unity, but he was met by hostility in both places by people who fault his own incendiary words as a contributing cause to the mass shootings AP Trump protests: President visits Texas and Ohio after mass shootings El Paso, University Medical Centre US President Donald Trump greets first responders as he visits El Paso Regional Communications Centre AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso, University Medical Centre An anti-Trump protestor holds a sign as police are lined up outside University Medical Centre Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso Demonstrators hold a sign as the motorcade carrying President Donald Trump departs a joint operations center after meeting with first responders after the El Paso mass shooting, Wednesday, Aug. 7, 2019, in El Paso, Texas. (AP Photo/Evan Vucci) Evan Vucci AP Trump protests: President visits Texas and Ohio after mass shootings El Paso Anti-Trump protesters hold a banner outside the makeshift memorial to the victims of the WalMart shooting that left a total of 22 people dead, in El Paso, Texas, on August 7, 2019. - President Donald Trump consoled victims of a mass shooting in Ohio on Wednesday but protesters and opponents denounced what they say is his extremist rhetoric on race and immigration. The president's trip to Dayton, where nine people were gunned down over the weekend, was to be followed immediately after by a stop in the border city of El Paso, Texas, where 22 were murdered. (Photo by Mark RALSTON / AFP)MARK RALSTON/AFP/Getty Images MARK RALSTON AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings Miami Valley Hospital, Dayton Demonstrators gather to protest the arrival of President Donald Trump outside Miami Valley Hospital after a mass shooting that occurred in the Oregon District early Sunday morning, Wednesday, Aug. 7, 2019, in Dayton. Twenty-four-year-old Connor Betts opened fire in Dayton early Sunday, killing several people including his sister, before officers fatally shot him. (AP Photo/John Minchillo) John Minchillo AP Trump protests: President visits Texas and Ohio after mass shootings El Paso Democratic presidential candidate Beto ORourke hugs a woman at a makeshift memorial outside Walmart honoring victims of the mass shooting there which left 22 people dead. Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso Anti-Trump protesters hold signs outside the makeshift memorial to the victims of the WalMart shooting that left a total of 22 people dead, in El Paso, Texas, on August 7, 2019. - President Donald Trump consoled victims of a mass shooting in Ohio on Wednesday but protesters and opponents denounced what they say is his extremist rhetoric on race and immigration. The president's trip to Dayton, where nine people were gunned down over the weekend, was to be followed immediately after by a stop in the border city of El Paso, Texas, where 22 were murdered. (Photo by Mark RALSTON / AFP)MARK RALSTON/AFP/Getty Images MARK RALSTON AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso Marisela Hernandez holds sign to protest the visit of President Donald Trump to the border city after the Aug. 3 mass shooting in El Paso, Texas, Wednesday, Aug. 7, 2019. Aiming to play the traditional role of healer during national tragedy, President Donald Trump paid visits Wednesday to cities reeling from the mass shootings. (AP Photo/Andres Leighton) Andres Leighton AP Trump protests: President visits Texas and Ohio after mass shootings El Paso, University Medical Centre An anti-Trump demonstrator holds up a placard outside the University Medical Center, where U.S. President Donald Trump holds a meeting with first responders in the wake of last weekend's mass shootings at a Walmart store, in El Paso, Texas, U.S., August 7, 2019. REUTERS/Jose Luis Gonzalez JOSE LUIS GONZALEZ Reuters Trump protests: President visits Texas and Ohio after mass shootings El Paso, University Medical Centre President Trump and First Lady Melania Trump greet PFC Glendon Oakley (second right), who saved several lives during the mass shooting in Texas AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings Miami Valley Hospital, Dayton Demonstrators chant as they protest the arrival of President Donald Trump outside Miami Valley Hospital after a mass shooting that occurred in the Oregon District early Sunday morning, Wednesday, Aug. 7, 2019, in Dayton. (AP Photo/John Minchillo) John Minchillo AP Trump protests: President visits Texas and Ohio after mass shootings El Paso, University Medical Centre An anti-Trump demonstrator holds up a placard as police block the area outside the University Medical Center, where U.S. President Donald Trump holds a meeting with first responders in the wake of last weekend's mass shootings at a Walmart store, in El Paso, Texas, U.S., August 7, 2019. REUTERS/Jose Luis Gonzalez JOSE LUIS GONZALEZ Reuters/Amanda Voisard Trump protests: President visits Texas and Ohio after mass shootings El Paso Beto ORourke consoles a man at the makeshift memorial outside Walmart Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso, University Medical Centre An anti-Trump demonstrator yells near police outside the University Medical Centre Reuters Trump protests: President visits Texas and Ohio after mass shootings El Paso TOPSHOT - El Paso residents protest against the visit of US President Donald Trump to the city after the Walmart shooting that left a total of 22 people dead, in El Paso, Texas, on August 7, 2019. - President Donald Trump consoled victims of a mass shooting in Ohio on Wednesday but protesters and opponents denounced what they say is his extremist rhetoric on race and immigration. The president's trip to Dayton, where nine people were gunned down over the weekend, was to be followed immediately after by a stop in the border city of El Paso, Texas, where 22 were murdered. (Photo by Mark RALSTON / AFP)MARK RALSTON/AFP/Getty Images MARK RALSTON AFP/Getty Images Trump protests: President visits Texas and Ohio after mass shootings Dayton President Donald Trump and First Lady Melania Trump arrive at Wright-Patterson Air Force Base AP Trump protests: President visits Texas and Ohio after mass shootings El Paso Makeshift memorial for victims of the shooting that left a total of 22 people dead at the Cielo Vista Mall Walmart AFP/Getty Images Trump protests: President visits Texas and Ohio after mass shootings Miami Valley Hospital, Dayton Demonstrators gather to protest the arrival of President Donald Trump outside Miami Valley Hospital after a mass shooting that occurred in the Oregon District early Sunday morning, Wednesday, Aug. 7, 2019, in Dayton. (AP Photo/John Minchillo) John Minchillo AP Trump protests: President visits Texas and Ohio after mass shootings President Trump greets Dayton Mayor Nan Whaley as he arrives at Wright-Patterson Air Force Base AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings Miami Valley Hospital, Dayton Demonstrators gather to protest the arrival of President Donald Trump outside Miami Valley Hospital after a mass shooting that occurred in the Oregon District early Sunday morning, Wednesday, Aug. 7, 2019, in Dayton, Ohio. Twenty-four-year-old Connor Betts opened fire in Dayton early Sunday, killing several people including his sister, before officers fatally shot him. (AP Photo/John Minchillo) John Minchillo AP Trump protests: President visits Texas and Ohio after mass shootings Dayton Damon Smith presents a message to President Donald Trump beside a makeshift memorial in Dayton AP Trump protests: President visits Texas and Ohio after mass shootings Miami Valley Hospital, Dayton Demonstrators gather in front of an inflatable "Baby Trump" to protest the presidents arrival AP Trump protests: President visits Texas and Ohio after mass shootings Miami Valley Hospital, Dayton Demonstrators gather to protest the arrival of President Donald Trump outside Miami Valley Hospital after a mass shooting that occurred in the Oregon District early Sunday morning, Wednesday, Aug. 7, 2019, in Dayton. President Donald Trump is headed to Dayton and El Paso, Texas on Wednesday to offer a message of healing and unity, but he will be met by unusual hostility in both places by people who fault his own incendiary words as a contributing cause to the mass shootings . (AP Photo/John Minchillo) John Minchillo AP Trump protests: President visits Texas and Ohio after mass shootings El Paso A photo of victim Javier Amir Rodriguez, a 15-year-old sophomore Getty Trump protests: President visits Texas and Ohio after mass shootings Dayton Demonstrators protest the visit of US President Donald Trump to the site of the mass shooting in Dayton, Ohio, on August 7, 2019. - Nine people were killed on August 4 in the city's popular Oregon District. (Photo by Megan JELINGER / AFP)MEGAN JELINGER/AFP/Getty Images MEGAN JELINGER AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso A message is left for Donald Trump AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso Signs and flags adorn the makeshift memorial for victims of the shooting that left a total of 22 people dead at the Cielo Vista Mall Walmart, in El Paso, Texas, on August 7, 2019. (Photo by Mark RALSTON / AFP)MARK RALSTON/AFP/Getty Images MARK RALSTON AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso People hug at the makeshift memorial AFP/Getty Trump protests: President visits Texas and Ohio after mass shootings El Paso People pray at the makeshift memorial AFP/Getty

The stocks of all three companies the president mentioned also dropped as traders tried to understand what the implications for them were.

Stocks had been wavering between gains and losses earlier after China said it would retaliate against the latest round of tariffs imposed by Washington.

China said Friday that it will also increase import duties on US-made autos and auto parts. The retaliation pulled global markets into negative territory.

Mr Trump’s current economic rating in a new Associated Press poll represents a 5 percentage point drop from the same time last year, but for a president who has struggled to win over a majority of American voters on any issue, the economy represents a relative strength.

Even some Democrats approve: Just 5 per cent of Democrats approve of his job performance overall, but 16 per cent approve of his handling of the economy.