Once-promising talks have ended with no deal to suspend Iran's nuclear program.

After three days of negotiations at the Intercontinental Hotel in Geneva, top diplomats from the U.S., Iran, France, the U.K., the European Union, Germany, Russia, and China will depart without an agreement to suspend or limit Iran's nuclear enrichment in exchange for temporary relief from international sanctions, after hopes had risen that such a deal was close.

With negotiations under way, Secretary of State John Kerry broke off his Middle East trip to fly to Geneva on Friday, and Russian Foreign Minister Sergei Lavrov followed today, raising speculation that a deal might be imminent.

Top Iranian diplomats had stoked those hopes, telling news outlets that sides would start drafting an agreement on Friday. The goal of these meetings was a "first step" agreement, as the U.S. called it, to ease tensions and relieve fears of the proliferation of nuclear weapons while a longer-term deal could be worked out over the next six months.

Talks will resume in three weeks, on Nov. 20. Kerry, European Union High Representative Catherine Ashton, and Iranian Foreign Minister Javad Zarif announced the end of this round at press conferences tonight.

The window of diplomacy will not stay open forever, Kerry told reporters.

French diplomats spoke up today against the deal that was on the table. French Foreign Minister Laurent Fabius told a French radio station that Iran opposed halting work on a nuclear facility and downblending some of its 20 percent-enriched uranium to 5 percent, which could still be used as nuclear reactor fuel.

An agreement to halt enrichment would have been a major step toward defusing Iranian nuclear progress that has raises serious concerns in Israel and elsewhere.

It also would have been a major achievement for Kerry, who will return to the U.S. without having convinced Iran to halt enrichment, and for Zarif, who will return to Iran without a deal to ease economic sanctions.