Iran's top nuclear official says Europe should accept an Iranian proposal to allow it to enrich uranium or risk a collapse of talks on Iran's nuclear program. The warning by Hassan Rowhani appears in an interview published today by the Financial Times. It comes as diplomats from Britain, France and Germany begin talks with their Iranian counterparts in Geneva, ahead of a more senior-level meeting in London on April 29. The three countries are leading EU efforts to defuse the crisis. The U.S. accuses Iran of trying to develop nuclear weapons. Uranium enrichment could be used for bombs or fuel for nuclear reactors. Iran says its program is only for energy purposes. In the interview, Rowhani -- head of the supreme national security council -- stopped short of saying Iran would resume uranium enrichment, which it has suspended while the talks continue.