US crude oil prices fluctuated slightly overnight on the news that President Trump would impose sanctions on Iran
The price fell in the hours before Trump's announcement as federal government forecasters raised their 2018 estimate for oil price to $US65.58 a barrel, a rise of 10.5 per cent.
Prices returned again following Trump's announcement although there will be more movement on oil in the next few months.
No one is sure just how high oil prices will go however once sanctions are defined a much clearer picture will emerge.
The Treasury said on Tuesday that sanctions against Iran's oil trade wouldn't be imposed against Islamic Republic for another six months.