By bne Tehran bureau The Iranian rial (IRR) weakened sharply on October 23 as the US dollar posted significant gains amid the looming threat of an all-out war with Israel. The US dollar climbed 2.77% to close at IRR 686,500 after hitting an intraday high of IRR 687,500, while the regional AED rose 3.5% to IRR 186,300, according to market data. Other currencies followed a similar trend, with the euro, pound and Canadian dollar also increasing against the rial in the latest downward spiral of the massively weakened Iranian currency. This bout of depreciation comes amid fears in the local Iranian…