MOSCOW - Global powers and Iran are close to a preliminary deal to rein in Tehran's nuclear program and should not pass up a "very good chance" to clinch it, Russian Foreign Minister Sergei Lavrov said in remarks broadcast on Saturday.His upbeat comments in a television interview came a day after a senior US official said it was possible a deal could be reached when negotiators meet in Geneva from Nov. 20.Six nations negotiating with Iran hope the talks can produce an agreement that would be the first step towards a comprehensive deal to end a decade-long standoff with Tehran and provide assurances it will not build nuclear weapons."Our common impression is that there is a very good chance that must not be passed up," Lavrov said of a recent discussion with European Union foreign policy chief Catherine Ashton, when asked whether the Geneva talks could be successful.