Mumbai, Feb 23 (PTI) The rupee gained 5 paise to settle at 90.89 against the US dollar on Monday, aided by a sharp fall in global crude oil prices and a weaker greenback amid renewed global trade-related uncertainties.

However, fresh geopolitical concerns due to escalated tension between the US and Iran, capped gains for the local unit, forex traders said.

At the interbank foreign exchange, the rupee opened at 90.76 and traded in a range of 90.67-90.90 against the greenback during the session. It eventually settled at 90.89, up 5 paise from its previous close.

The rupee plunged 26 paise to settle at 90.94 against the US dollar on Friday.

"Rupee rose to 90.67 but was not able to sustain gains as equities did not sustain the morning highs as debt yields rose. Despite the favourable verdict from the US Supreme Court, the rupee did not make any big gains, and the dollar was bought on every dip by importers and other buyers like the FPIs," Anil Kumar Bhansali, Head of Treasury and Executive Director, Finrex Treasury Advisors LLP, said.

The rupee is expected to be in the range of 90.60 to 91.00, he said.

Meanwhile, the dollar index, which gauges the greenback's strength against a basket of six currencies, was trading lower by 0.32 per cent at 97.47.

Brent crude, the global oil benchmark, was down 0.39 per cent at USD 71.49 per barrel.

On the domestic equity market front, Sensex went up 479.95 points to settle at 83,294.66, while the Nifty advanced 141.75 points to 25,713.

On Monday, foreign institutional investors purchased equities worth Rs 3,483.70 crore, according to exchange data.

India's forex reserves jumped USD 8.663 billion to hit a new all-time high of USD 725.727 billion in the week ended February 13, the RBI said on Friday. PTI TRB HVA

Exchange rate volatility: Rupee edges higher as oil weakness supports the currency while geopolitical tensions cap gains. Exchange rate movement recorded the rupee appreciating modestly against the US dollar, settling marginally stronger after declines in global crude oil prices and a softer dollar. Market dynamics included importer and foreign portfolio investor dollar purchases on dips, rising domestic debt yields that capped gains, and geopolitical tensions limiting upside. The report also notes that India's foreign exchange reserves rose to a new high, a factor relevant to reserve adequacy and forex market liquidity.