US President Donald Trump has signed an order doubling tariffs on steel and aluminium imports from 25% to 50%. The move hikes import taxes on the metals - key inputs in everything from cars to canned food - for the second time since March.

The president first announced the doubling of tariffs on aluminum and steel at a rally in Pennsylvania last week.

President Donald Trump has raised steel and aluminum tariffs to 50% from 25%, following through on a pledge to boost US import taxes to help domestic manufacturers.