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The earlier SWIFT ban is widely seen as having helped persuade Iran's government to negotiate over its nuclear programme. The ban was one of the first sanctions Tehran asked to be lifted, points out Mark Dubowitz of the Foundation for Defence of Democracies, a Washington-based think-tank. Though some of the banks blocked from SWIFT managed to keep moving money by leasing telephone and fax lines from peers in Dubai, Turkey and China, or (according to a Turkish prosecutor's report) by using non-expelled Iranian banks as conduits, such workarounds are a slow and expensive pain. And the sanctions prompted Western banks to stop conducting other business with the targeted banks.
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