By Lawrence White

LONDON (Reuters) -Britain’s Financial Conduct Authority (FCA) has fined Metro Bank 16 million pounds ($20.51 million) for failings in its anti-money laundering controls, in the latest blow to the struggling mid-sized lender.

The bank failed to have the right systems and controls to adequately monitor more than 60 million transactions, with avalue of over 51 billion pounds, for money laundering risks between 2016 and 2020, the FCA said.

Metro Bank, which launched in 2010 to battle Britain’s incumbent lenders, has struggled in recent years, leading to a rescue deal last October, but has shown signs of a turnaround with a return to profit forecast for the fourth quarter.

Since identifying the issues, Metro Bank has put in place processes to remediate the flaws, the watchdog said.

Metro Bank shares fell 3% in early trading on Tuesday, against a 0.5% fall in the benchmark FTSE 100 index, but were still up 128% in the year to date as its turnaround continues.

“Metro’s failings risked a gap being left in our defence against the criminal misuse of our financial system. Those failings went on for too long,” Therese Chambers, joint executive director of enforcement and market oversight, said in a statement.

The bank automated its systems for monitoring transactions in 2016, the FCA said, but the system did not work and transactions made on the same day an account was opened were not monitored.

“The conclusion of these enquiries draws a line under this legacy issue, allowing the bank to move forward and fully focus on the future, building on the solid foundations it has already laid,” Daniel Frumkin, Metro Bank CEO said in a separate statement.

Metro Bank in its trading update for the third quarter said that it still expects to meet its performance forecasts for the year.

The bank has shifted toward higher yielding specialist mortgages and commercial lending, Frumkin said.

($1 = 0.7803 pounds)

(Reporting by Lawrence White, editing by Sinead Cruise, Louise Heavens and Sharon Singleton)