Predictably, the potential deal has attracted a lot of criticism, particularly as violence flares in Yemen where rebels, allegedly backed by Iran, take control of key parts of the country, despite Saudi-led airstrikes against them.
Against this background of rising tensions in the Middle East, predominantly Sunni nations, such as Saudi Arabia, feel "betrayed" by Western nations trying to seek a deal with Shia-majority Iran, Soussa said.
But any belief that a deal could create more stability in the Middle East was misplaced, he added.
"There is a view that a deal will mean a warming up of relations across the Gulf and that, all of a sudden, the Sunni-Shia rivalries (such as those between Iran and Saudi Arabia) will go away and everyone will be running away into the sunset. I think that's completely wrong," Soussa warned.
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He said the negotiations could drive the Saudis to develop a coalition with Egypt and others, in an effort to create a Sunni front in the face of increasing Iranian influence in the region.
"So rather than making sectarian or political tensions diminish in the region, I think a deal could enflame those tensions," he added.