Sliding for the fourth straight session, the rupee tanked 76 paise to close at 76.93 on Monday, after touching its lifetime low of 77 against the US dollar, as crude oil prices climbed to multi-year highs amid the Russia-Ukraine crisis. Global oil prices soared past USD 120 per barrel amid the US and European nations mulling a ban on Russian energy imports.Sustained foreign fund outflows and a lacklustre trend in domestic equities also weighed on investor sentiment, forex traders said. At the interbank foreign exchange market, the rupee opened at 76.85 against the American currency and slumped to an all-time low of 77, before closing at 76.93, down 76 paise from the previous close. "The Indian rupee has plummeted to a lifetime low against the US dollar as the deepening Russia-Ukraine conflict has sapped risk appetite in the market while prompting safe-haven flows into the US dollar," said Sugandha Sachdeva, Vice President - Commodity and Currency Research, Religare Broking Ltd. Besides, the parabolic rise in crude oil prices towards multi-year highs and spiralling commodity prices are fuelling inflationary risks, which is a key headwind for the rupee-dollar exchange rate, Sachdeva added.