Indian stock markets opened on a negative note on Friday and extended losses tracking weak Asian equities and disappointing data on retail inflation for April and factory output for March.

The S&P BSE Sensex was trading at 25,538, down 387 points, or 1.50 percent, while the NSE Nifty had edged 98 points, or 1.24 percent, lower at 7,802 at around 12.35 p.m.

The bank indices on both the stock exchanges (S&P BSE Bankex and NSE Nifty Bank) were down one percent as analysts saw the surge in inflation as limiting the scope for a rate cut by the Reserve Bank of India (RBI) when it meets for its monetary policy review meeting in June.

SBI, Bank of Baroda, ICICI Bank, HDFC Bank and PNB were trading in the red.

Retail inflation increased to 5.39 percent in April from 4.83 percent in the previous month, while food inflation rose to 6.21 percent from 5.2 percent in March, according to the data released by the Indian government after trading hours on Thursday.

"These price outcomes reinforce our expectations that the Reserve Bank of India will keep rates unchanged in June, with focus primarily on policy transmission after slew of measures unveiled in April," Radhika Rao, economist, Group Research, DBS Bank Ltd. in a note on Friday.

The second bi-monthly monetary policy statement will be announced on June 7 and the third on Aug. 9. 

Asian stock markets declined tracking crude oil prices that retreated on Thursday. A sharp fall in Apple share price also added to the downbeat mood on the bourses.

"Shares of Apple dropped below $90 on Thursday for the first time since 2014 as Wall Street worried about slow demand ahead of the anticipated launch of a new iPhone later this year. The company's market capitalization has fallen by more than $200 billion so far this year," Money.com reported on Thursday. 

Factory output growth slowed down to 0.1 percent in March from 2 percent in the previous month. The full-year growth rate was 2.4 percent in 2015-16, down from 2.8 percent in the previous financial year.