As Iran deal looms, is it time to worry about oil?

Iran deal by summer's end?
Iran deal by summer's end?   

The U.S. wants a deal and Iran wants a deal, but again despite another deadline set for Monday the two countries have yet to agree over terms in nuclear talks as night falls in Tehran.

The failure to strike a deal means maintaining sanctions, which for years have restricted Iranian oil exports and kept millions of barrels out of the global supply. But as the White House remains confident a deal is expected soon, many wonder how imminent the flood of Iranian oil might be.

"The longer this gets dragged out, we are pushing out the timeline for the return of those barrels," RBC Capital Market's global head of commodity strategy, Helima Croft, told CNBC's "Power Lunch."

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"It's going to be six to eight months post-deal in terms of modifying those facilities before those barrels come back," she said.

Beyond the delay caused by Iranian facilities, Croft says some are overlooking the political ramifications of allowing oil to flood an already oversupplied market.

"There's no way the [European Union] and the Obama administration is going to sign on to have those barrels flowing right after it's signed," she said.

But beyond the question of when those oil exports would hit the market is the question of what sort of an impact it might have on global oil production as it runs at record production of 92 million barrels a day.

While some estimate Iran's oil production capabilities to be near 1 million barrels per day, Croft offers estimates at about half that but says even that would be enough to further drop prices.

"If you're oversupplied by 1.5 million barrels, adding an additional 500,000 barrels doesn't make your balance particularly pretty," she said.