The US president signs a proclamation to impose tariffs on some steel and aluminium imports, telling reporters 'we have to do something' to fix a $500bn trade imbalance with China. However, Donald Trump's White House press conference descended into laughter when he told the president of a local steel union, Scott Sarge, 'Your father Herman is looking down, he’s very proud of you.' Sarge pointed out that his father was still alive, at which point Trump said in that case he must be even more proud. The president then offered to arm wrestle another industry figure as he stepped up to the podium.