US President Donald Trump will face off with Democrat Joe Biden in Iowa as the pair hold competing rallies in the key swing state.
Biden, kicked off a three-stop national tour ahead of next year's presidential election by describing Trump as an 'existential threat' to the US.
But as he left the White House, Trump hit back at the veteran Democrat, describing him as a 'dummy'.
'I heard Biden who is a loser. Look, Joe never got more than 1 per cent, except Obama took him off the trash heap.
'He looks different that he used to. He acts different than he used to. He's even slower than he used to be.'
'Joe Biden is a dummy.'
The veteran Democrat has attacked Trump for his tariff policy and its impact on Iowa farmers.
'Iowa farmers have been crushed by his tariff war with China and no one knows better than the folks in Iowa. He thinks that being tough is great, well it's really easy to be tough when someone else absorbs the pain: farmers, manufacturers, the automobile industry,' Biden said.
Biden added that Trump 'backed off his threat of tariffs to Mexico basically because he realized he was likely to lose' in manufacturing states such as Michigan and Ohio.
Biden will spend his day campaigning in eastern Iowa, according to his schedule, while Trump will head for the western side to make remarks on renewable energy before flying to central Des Moines for a dinner and fundraiser with the state's Republican Party.
With CNN, AP
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