VIENNA (AP) — A new and seemingly promising U.N probe of allegations that Iran worked on atomic arms has stalled, diplomats say, leaving investigators not much further than where they started a decade ago and dampening U.S. hopes of reaching an overarching deal with Tehran by a November deadline.

Expectations were high just two weeks ago, when chief U.N. nuclear inspector Yukiya Amano emerged from talks in Tehran with Iranian President Hasan Rouhani saying Iran had given “a firm commitment” to cooperation and suggesting that years of deadlock had been broken.