(CNN) - The historic six-month agreement over Tehran's nuclear program may begin a new era of relations with Iran, but it will be a long road back for the country's most vital sector, oil.
Iran produces about two and half million barrels a day - far off its 4-million-barrel-per-day peak a decade ago. Output is hovering at a level last seen at the end of Iran's war with Iraq. With North Sea Brent crude averaging over $100 a barrel for a record three years running, the sanctions on energy alone are costing Tehran about $50 billion in lost annual revenue.
"During the six month phase, the oil sanctions that will remain in place will continue to cause over $25 billion in lost revenues to Iran or over $4 billion a month," he said.
With every year that has passed, the screws have been tightened by Washington and the countries of the European Union. It was not only sanctions against oil, but also blocking Iran's ability to secure shipping insurance and to trade in U.S. dollars and euros. That economic isolation, many Middle East strategists I have spoken with suggest, is what brought Iran's new government to the negotiating table.
Despite the deal breakthrough, U.S. Secretary of State John Kerry said most of the sanctions will stick as the world gauges the intentions of this relatively new administration in Tehran.
The message is clear: the pressure remains, but if all goes well, in a half year's time Iran can expect more in return for transparency.
It is still early days, but this country of nearly 80 million people has been described as potentially being the Germany of the Middle East with plenty of natural resources - that is, if it can emerge from years of economic isolation.
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