March 13 (Reuters) - India's equity benchmarks fell on Friday and were on course for their biggest weekly drop in about 15 months as escalating Middle East conflict kept Brent crude prices elevated, driving investors out of risk assets.

The Nifty 50 and BSE Sensex lost about 1.1% each to 23,356.05 and 75,195.11, as of 9:58 a.m. IST. The indexes have lost 4.5% and 4.8%, respectively, this week, on course for their biggest drop since December 2024.

Fifteen of the 16 major sectors declined while the broader small-caps and mid-caps dropped 1.8% and 1.5%. 

Brent crude oil futures hovered around the $100 per barrel hit in the previous session, due to the raging Mideast conflict and disruption to supplies through the crucial Strait of Hormuz. [O/R] 

High weight financials, banks, private banks lost about 1.5% each, while state-owned lenders slid 2%.

Auto stocks fell 1.6%, extending losses to a third day, on concerns over crude price spike and liquefied natural gas supply disruption. 

Metal index dipped 3%, with aluminium makers Hindalco and Nalco dropping 4.5% each, tracking a drop in global aluminium prices. 

The session's losses capped the weekly gains of Hindalco and Nalco, driven by supply risks from the Middle East. 

"For investors, the worry is that a broader energy shock could reignite inflation, much as it did after the Russia-Ukraine war, forcing central banks to keep monetary policy tighter for longer," said Ross Maxwell, global strategy operations lead at VT Markets.

"That would pressure equity markets and strain energy-importing economies such as India," Maxwell said. 

Among stocks, Balaji Amines lost 3.5% after flagging major ammonia procurement disruptions linked to the Mideast conflict.

Bucking the broader trend, Kalpataru jumped 8.5% after signing a redevelopment project in Mumbai, with a gross development value potential of 14 billion rupees.

Index heavyweight Reliance Industries rose 0.4% helped by positive commentary from brokerages Jefferies and Motilal Oswal around its defensive qualities, potential refining and petrochemical margin gains due to elevated product cracks.

(Reporting by Vivek Kumar M and Bharath Rajeswaran; Editing by Sumana Nandy and Nivedita Bhattacharjee)

By Bharath Rajeswaran and Vivek Kumar M