WASHINGTON (AP) — The failure of negotiations between six world powers and Iran over its disputed nuclear program has jumpstarted the congressional push for even tougher sanctions aimed at crippling the economy in Tehran.

The latest talks this past weekend in Kazakhstan proved inconclusive as the United States, Russia, China, France, Britain and Germany pressed Iran to significantly limit its production and stockpiling of uranium enrichment. The international community fears Tehran is developing a nuclear weapon; Iran insists its work is for peaceful purposes.