Lifting oil sanctions against Iran could "reorder" the Middle East, bringing to end 30 years of poor relations with the U.S., the former deputy secretary-general of the United Nations (UN) said on Friday.
Mark Malloch-Brown, who currently chairs FTI Consulting for Europe, the Middle East and Africa, said the UN Security Council's interim deal with Iran was the "most promising" development in the Middle East.
"I think there is some progress... I think the U.S. and Iran are beginning to recognize a real strategic interest in trying to push this through," Malloch-Brown told CNBC.
"There is always a caveat: if the U.S. Senate lets them," he said.
The six-month deal, which took effect on Monday, saw Iran agree to limit its nuclear enrichment program in exchange for certain international sanctions being lifted.
The country is still only allowed to sell 1 million barrels per day of crude oil, but if the deal proves successful, a long-term pact could be struck, with all sanctions — including those on oil sales — being lifted.
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Malloch-Brown said a warming of relations between the West and Iran could change the face of the Middle East.
"At the extreme end, it might even reorder the Middle East. Traditionally, Iran was a great friend of the U.S. This has been a 20- or 30-year hiatus where it has been very different. But we may see that order of things coming back," he said.
He was less sanguine however about prospects for other Middle Eastern nations, describing Iran's progress as both the "most promising" and the "most improbable".
"We have got a series of very nasty situations in the Middle East," Malloch-Brown said.
"Egypt: the bombs yesterday were just an indication of how unstable and how unresolved the political situation there is. Syria: the negotiators are having huge difficulties making progress on this very violent, very intractable conflict. The Israelis and Palestinians are only talking to each other because U.S. Secretary of State John Kerry insists they do."
(Read more: Israeli PM: Why we cannot do business with Rouhani)
Malloch-Brown spoke to CNBC from the annual World Economic Forum in Davos, Switzerland. He is a specialist in emerging markets and international affairs and was formerly a development specialist at the World Bank, as well as a U.K. government minister.