The rupee depreciated 20 paise to an all-time low of 96.90 against the US dollar in early trade on Wednesday weighed down by a strong dollar and elevated crude oil prices amid simmering Iran-US tensions.Forex traders said the outflow by FIIs and decline in equity benchmark indices also pressured the rupee.At the interbank foreign exchange market, the rupee opened at 96.89 against the US dollar, then slipped further to 96.90, registering a fall of 20 paise from its previous close.On Tuesday, the Indian rupee slumped for the eighth consecutive session and ended 50 paise down at its record low of 96.70 against the US dollar.Meanwhile, the dollar index, which gauges the greenback’s strength against a basket of six currencies, was trading at 99.262, up 0.01 per cent.On the domestic equity market front, Sensex tanked 517.11 points to 74,667.51 in early trade while Nifty dropped 152.45 points to 23,475.80.