Much rides on attempts to broker a deal on Iran's nuclear program.
American officials and their Iranian counterparts are in Lausanne, Switzerland, attempting to agree on an accord to limit Iran's nuclear program by Tuesday's deadline. A more comprehensive deal is scheduled to be done by the end of June.
The sanctions have significantly reduced oil and natural-gas exports from Iran, cutting Tehran's oil export revenue nearly in half. The sharp drop in global oil prices have also hit Iran.
And, while the recent military intervention by Saudi Arabia in Yemen prompted a brief spike in oil prices due to supply disruption concerns, there is also thinking a deal with Tehran could flood the market with Iranian crude.
"The implications for markets are quite profound if there is an agreement," Cliff Kupchan, chairman of the Eurasia Group, tells CBS Moneywatch. "Within a year or two, 1.2 million barrels a day of Iranian crude oil that was taken off the market will return."
If the deal fails, "we could have Iran building its (nuclear) program again; we could have Israel talking about (military) strikes and you'd have just the opposite effect," with oil prices rising.
That said, there's a compelling argument to be made that the steep drop in oil prices, which had crude falling by more than 50 percent last year, can largely be chalked up to increased oil production, with a chart published Monday by the U.S. Energy Information Administration showing U.S. output up by 1.2 million barrels a day last year to 8.7 million barrels a day.
On Tuesday, crude futures for May delivery fell 19 cents, or 0.4 percent, to close at $48.68 a barrel on the New York Mercantile Exchange.