National Australia Bank faces the prospect of further remediation and a huge fine after it revealed it might have made multiple breaches of counter-terrorism and anti-money laundering laws.

The lender said in its annual report on Friday it might have been involved in a breach or alleged breach of laws governing bribery, corruption and financial crime.

It said it had provided documents and information to the financial intelligence watchdog.

NAB said it was unsure how deeply the issue had run and how significant any AUSTRAC penalty would be.

Commonwealth Bank was fined a record $700 million in 2018 for serious breaches of the same laws.

NAB said it had self-reported “a number” of issues to finance intelligence agency AUSTRAC, and was investigating and remediating several counter-terrorism and anti-money laundering breaches.

The bank accepted any confirmed wrongdoing would further harm its reputation and bottom line, both of which have already copped a hiding in the wake of misdeeds uncovered by the financial services royal commission.

“The potential outcome and total costs associated with the investigation and remediation process remain uncertain,” the bank said in its annual report.

“Given the large volume of transactions that the group processes, the undetected failure of internal AML/CTF controls, or the ineffective implementation or remediation of compliance issues, could result in a significant number of breaches … and significant monetary penalties.”

Shares in the bank had dipped by 1.26 per cent to $27.45 by 11.30am (ADST) on Friday.

-AAP