Shares of Yes Bank slumped as much as 13 percent to hit its new 52-week low of Rs 117.40 on NSE after international brokerage UBS retained its 'sell' rating on the stock while lowering its price target sharply by 47 percent to Rs 90 from Rs 170 before.

In the morning trading session, the stock was the biggest loser on BSE's Sensex as well as NSE's Nifty 50. The private bank's share price has fallen 30 percent since the start of 2019, and has seen a 62 percent drop in the last one-year's time.

The brokerage slashed its price target on the lender as it projects weak earnings for the bank. UBS also downgraded its price target for IndusInd Bank, on the same grounds, from Rs 1,700 to Rs 1,400.

"We raise FY20 credit cost estimates for Yes Bank to 250 bps from 200 bps and for IndusInd Bank to 150 bps from 100 bps as network risks drive credit cost estimates higher," it said.

Shares of IndusInd Bank fell by close to 8 percent to Rs 1,440 apiece on NSE.

The research firm also said that it sees the next level of risk from leveraged corporates' related companies. Hence, it lowered its earnings estimates for Yes Bank and IndusInd Bank by 79 percent and 53 percent, respectively. Its earnings projection for the financial year 2020-21 for the two banks declined to 7.3 percent and 8.6 percent, respectively.