The price of West Texas Intermediate crude reached a low of $61.31 a barrel Tuesday. That was down about 20 percent from Oct. 3 when oil was trading at $76.41 per barrel at the market close.
Trump re-imposed sanctions on Iran Monday, and in the lead-up to the announcement analysts feared global oil prices could spike.
The sanctions aim to cut Iran's oil industry off from international sales. The penalties also cover hundreds of Iranian and Iran-linked individuals, entities and aircraft.