Shares of Barclays Plc have been declining for two weeks now following a lawsuit filed by New York attorney general, Bloomberg reported.

The British bank experienced a 79 percent decline in its "dark pool" or trading venue after the state of New York accused the bank of allegedly lying to its customers by giving priority to high-frequency traders.

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Dark pool is the banking term for trading venues anonymously, the information about the trade is only given after the shares has been traded, thus avoiding leakage of information.

U.S. Attorney General Eric Scheiderman filed a complaint against Barclays on June 25, claiming that the bank has lied to its customers by misleading clients during the dark pool, in an effort to expand its revenue.

Anthony Jenkins, Barclays chief executive officer, addressed the allegations stating that the bank will deal with any consequences resulting from its actions, according to the Motley.

Barclays' LX, one of the bank's trading systems, experienced a drop of 66 percent in terms of shares over the week from 197 million to 66.4 million shares, following another big drop in shares of 37 percent from the week, according to a report from the Financial Industry Regulatory Authority.

Barclays' shares have also dropped 23 percent in London early in the year. Because of several declines in Barclay's shares, the bank is now the worst performing out of Britain's five largest banks.

Several bank and brokers have admitted that they stopped trading in Barclays dark pool after the lawsuit was filed, including Credit Suisse, Royal Bank of Canada and Investment Technology Group, among others.

Tagsbarclay plc, shres, Lawsuit