TEHRAN, Iran (AP) — Traders say Iran's currency has hit a record low against the U.S. dollar in street trading.

The rial dropped 5 percent in a single day, to 21,500 rials to the dollar.

The collapse of the Iranian currency is a sign of the effect Western sanctions over Iran's nuclear program. The West suspects Iran is aiming to build nuclear weapons. Iran denies that.

On July 1, the European Union banned import of Iranian oil, and the U.S. tightened sanctions against Iran's banks.

On Sunday the governor of Iran's central bank, Mahmoud Bahmani, said he would announce a new official rate for the dollar, but he did not give a figure.

The current official rate is 12,260 rials to the dollar, used only for special purposes like importing food and medicine.