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An Iranian oil minister attends an OPEC conference in 2005. Iran has threatened to cut off access to the Strait of Hormuz if the U.S. goes through with its plans for further sanctions. - 

Steve Chiotakis: Iran says if it has to, it'll block the flow of oil through the Strait of Hormuz -- a waterway that borders the country, and channels almost 20 percent of the world's oil. The strait is the link from the oil-rich Persian Gulf to the rest of the world. Iran has threatened to send military ships to block that strait if President Obama signs a bill to impose sanctions to keep Iran from making nuclear weapons.

Marketplace's Nancy Marshall-Genzer has more on a battle between Washington and Tehran that could hit all of us in the wallet.

Nancy Marshall-Genzer: Oil prices started rising as soon as Iran threatened to close the Strait of Hormuz. If Iran made good on its threat, oil prices would go through the roof.

Chris Skrebowski is an oil industry analyst with Peak Oil Consulting.

Chris Skrebowski: You'd have hysteria in the market. And when you have hysteria in the market the price does really silly things. It would go sailing up but, to where I can't tell you.

But Skrebowski says Iran isn't likely to make good on its threat, because it wouldn't be able to ship its oil, either.

And President Obama could tone down the sanctions; even waive them if they caused a spike in oil prices. He sure doesn't want that in an election year.

In Washington, I'm Nancy Marshall-Genzer for Marketplace.