Iran's first chance to unveil new oil and gas investment opportunities to Western oil companies - a widely anticipated London conference - has been delayed until November from early April, industry sources said on Tuesday, Reuters reported.
Tehran wants Western oil companies to revive its giant ageing oilfields and develop new oil and gas fields once sanctions are lifted and is improving its oil investment contract in order to lure them in.
The major OPEC producer has started implementing a nuclear deal with world powers, a step towards a broad settlement which could lead to the end of sanctions.
Tehran's leading contract negotiator Mehdi Hosseini told Reuters in December that the London conference would offer international oil companies the first opportunity to see Tehran's more attractive commercial terms.
The conference organizer was not immediately available to comment on the reason behind the delay.
Western sanctions imposed in 2012 on Iran for its nuclear program have choked Tehran's production - output is down a million barrels per day (bpd) since the start of 2012 to 2.7 million bpd - and lost it billions in oil revenue.
Top Iranian officials say the country can raise production to 4 million bpd within six months of sanctions being lifted. Western experts are more conservative, saying 3 million to 3.5 million bpd is more likely.
Encouraged by a preliminary nuclear deal struck between Iran and Western powers in November, Tehran and Big Oil have wasted no time making contact, in the hope of a full lifting of sanctions.
Paolo Scaroni of Italy's Eni was the first Western CEO to meet publicly with Iranian Oil Minister Bijan Zanganeh, on the sidelines of a meeting of the Organization of the Petroleum Exporting Countries last month.
Eni, Royal Dutch Shell and Total have already developed some of Iran's oilfields from scratch.
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