Canberra/Washington | Trade Minister Don Farrell is seeking talks with his US counterpart “as soon as is humanly possible” after Donald Trump followed through on threats to impose more tariffs on three of America’s biggest trading partners, and flagged further moves that could hit Australian pharmaceutical and aluminium exports.

The US president’s executive order applying tariffs of 25 per cent on all imports from Canada and Mexico – with the exception of Canadian oil and energy products which will face a 10 per cent levy – could affect Rio Tinto’s exports from its Canadian operation.