(Reuters) - Shares in U.S. banks fell on Wednesday, with the S&P 500 bank index <.SPXBK> hitting its lowest level since late 2016, after JPMorgan Chase (>> JPMorgan Chase & Co.) and Bank of America Corp (>> Bank of America Corp) warned of revenue weakness in the current quarter.

The bank index fell as much as 2.34 percent.

Bank of America and JPMorgan each fell more than 2 percent and were the biggest drags on the S&P 500 <.SPX>. Goldman Sachs (>> Goldman Sachs Group Inc), which is in the S&P financial sector index <.SPSY>, fell 3.7 percent after it gave a trading update.

JPMorgan's trading revenue has fallen 15 percent so far in the second quarter, its chief financial officer, Marianne Lake, told investors at a conference. She would not provide a prediction for June.

Bank of America Chief Executive Officer Brian Moynihan, meanwhile, told investors the bank's second-quarter trading revenue would be lower than a year ago.

"It's especially difficult because of the year-over-year comparison. The first and second quarter in 2016 were fairly busy on the trading front," said R.J. Grant, head of trading at Keefe, Bruyette & Woods in New York.

Investors were disappointed that JPMorgan's CFO did not predict a turnaround for June, Grant said.

"People are digging in for a bit of a slower summer here," he said. "If the big banks don't see anything on the horizon, then it potentially does not bode well for others. Volatility is non-existent. It's difficult to generate trading volumes or commissions or when the VIX is at historically low levels."

The U.S. stock market's main gauge of investor anxiety closed at its lowest level in over two decades on May 8. The CBOE Volatility Index <.VIX> was up 4.8 percent at 10.88 on Wednesday.

Goldman Sachs President David Solomon declined to give specifics about the bank’s trading business at an investor conference, but said subdued volatility - which depressed client activity in the first quarter - continued into April and May.

JPMorgan shares were last down 2.5 percent at $81.84 after hitting their lowest level since Dec. 2, with trading volume 1.3 times the 10-day moving average.

Bank of America shares were down 2.9 percent at $22.17 after earlier hitting a low of $22.09, also in heavy trading.

Citigroup Corp (>> Citigroup Inc) was down 2 percent at $60.38 while Huntington Bancshares Inc (>> Huntington Bancshares Incorporated) was the second biggest percentage loser in the bank subsector with a 2.6 percent drop.

Goldman Sachs shares hit their lowest point since late November and were last down 3.7 at $210.43 after hitting a low of $209.62. Trading volume in the stock was 1.8 times its 10-day moving average.

(Reporting by Sinead Carew, David Henry, Dan Freed and Olivia Oran; Editing by Meredith Mazzilli and Paul Simao)

By Sinead Carew