Mumbai, July 21 -- Foreign portfolio investors (FPIs) raised shorts on the Nifty Bank after major private banks reported a compression in net interest margins (NIMs)-the difference between interest earned on loans and paid on deposits-during the June quarter.

These investors net sold Nifty Bank futures worth Rs.1,201 crore on Monday, after buying futures worth a net Rs.1,441 crore on Friday, the day before lenders such as HDFC Bank, ICICI Bank, Kotak Mahindra Bank and Axis Bank reported their June-quarter results.

The selling in Nifty Bank futures was accompanied by an overall provisional sale of Rs.1,121 crore in the cash market by the cohorts on Monday.

This caused the Bank Nifty to fall by 1% to 57,945, with HDFC Bank, Axis Bank and...