The Iranian currency, battered by international sanctions and domestic turmoil, fell to new lows on Monday, triggering a new round of accusations of mismanagement among Iranian politicians.

The currency responded in part to what some Iranian traders interpreted as tougher talk from U.S. and Israeli officials, as well the Iranian central bank's inauguration of a new currency exchange in Tehran on Sept. 24.

The Iranian rial rate fell on Monday to as low as 33,500 rials to the dollar on informal currency bazaars and exchanges, down 13% on the day, after already falling sharply last week, according to traders in Tehran and currency websites.

The official rate—available in limited amounts for students and tourists traveling abroad—remained at the same 12,260 rials per dollar it has been at for several years.

Last week, President Barack Obama said at the United Nations that the U.S. will "do what we must" to prevent Iran from getting an atomic weapon. This was followed by hints by Israel's Prime Minister Benjamin Netanyahu that Israel could strike by mid-2013 if Tehran keeps up with its nuclear program.