Donald Trump says oil prices will plummet below pre-conflict numbers, if other nations join his economic isolation of Iran.

Speaking to the UN General Assembly, the US President said he must choose between letting Iran rebuild a far greater country or annihilate them.

Trump says until it stops attacks on commercial shipping and relinquishes its nuclear ambitions  Iran must be economically isolated.

US correspondent Dan Mitchinson says Trump's made plenty of threats against Iran over the last few months, and it's prompted scepticism among experts.  

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