In less than two weeks, Iran's biggest oil buyers will lose access to the London-based insurance market that protects 95 percent of the world's tankershipments against oil spills or catastrophiccollisions.

　　Barring an unexpected last-minute deal to relax European Union sanctions, Europe's Protection and Indemnity (P&I) clubs will be unable to insure vessels carrying Iranian crude from July 1, an unforeseen but ultimately critical side effect of EU sanctions to punish Iran for its nuclear program.

　　Europe's Protection and Indemnity (P&I) clubs：欧洲的保险与理赔俱乐部

　　In an extreme scenario, exports from OPEC's second-largest supplier -- already curtailed by separate U.S. sanctions and an EU import ban -- could grind to a halt next month as overseas oil companies cannot afford to take the risk of multibillion-dollar liabilitiesarising from an uninsured incident.

　　grind to：把…磨成…

　　Such an outcome seems unlikely. In Japan, which now buys about a fifth of Iran's exports, legislatorsare expected to approve unprecedented government guarantees to insure shipments later this month.

　　But no other country has announced similar arrangements, and buyers in South Korea and India say they will have to stop loading any new cargoes from July without a solution.

　　Despite the risks, however, oil markets appear blase: Since April, Brent crude prices have slumped more than 20 percent to trade below $100 a barrel for the first time since early 2011; in a straw poll by Reuters, none of the five analysts who provided forecastsfor Iranian exports expected more than a modest dip in sales in July and the rest of the year.

　　in a straw poll by:民意调查

　　"Insurance issues may affect exports on top of volumetrictargets, resulting in lower-than-expected Iranian exports, but as time passes market participants may find ways to deal with sanctions and exports may increase," Seth Kleinman at Citi said.

　　For the moment, traders are betting that reduced demand resulting from Europe's debt crisis, near-record Saudi oil production and a boom in North American output are more than sufficient to offset the estimated drop of 1 million barrels per day (bpd) in Iran's exports since last year.

　　resulting from：来源于……

　　Group of Eight nations have also made clear they could release emergency oil reserves quickly if supplies are endangered.

　　In effect, market sentimenton Iran has swung from one extreme to the other. The fears earlier this year of an immediate Israeli military attack on Iran have been replaced by what some analysts warn is dangerous complacency.

　　swung from：在……范围内波动

　　"Our view is that a large part of the lower Iran exports is already priced in," said Hans van Cleef, energy economist at ABN AMRO, who declined to provide a forecast. "The price effect on July 1st will therefore be very limited."

　　ABN AMRO：荷兰银行

　　More broadly, dimmer prospects for a resolution to high-level nuclear talks and growing risks of instability stemmingfrom Syria's turmoilmay be underestimated.

　　high-level nuclear talks：核计划高级别谈判

　　"I think it's a lot more volatile than the market recognizes," Barclays analyst Helima Croft said.

（编辑：何莹莹）