Mark Zandi thinks Trump has about a week to strike an Iran deal before the US has bigger problems.
Absent a peace deal, oil prices could soar again, triggering a US recession, he said.
Other forecasters have warned that it won't be long before economic damage from the war is more visible.
The halting peace negotiations between the US and Iran need to result in a deal soon if the US is going to avoid deeper economic pain.
That's according to Moody's top economist Mark Zandi, who said Donald Trump has about a week to secure a peace deal before the effects of the war make it more likely that the economy will fall into a recession.