WASHINGTON (Reuters) - Standard Chartered Plc has agreed to pay $1.1 billion to U.S. and British authorities for conducting illegal financial transactions that violated sanctions against Iran and other countries, government authorities announced on Tuesday.

FILE PHOTO: A logo of Standard Chartered is displayed at the financial Central district in Hong Kong, China November 23, 2017. REUTERS/Bobby Yip/File Photo

The settlement by the London-based bank is among the most severe imposed for sanctions violations, some of which occurred not long after Standard Chartered settled similar charges in 2012.

“The circumstances that led to today’s resolutions are completely unacceptable” and “not representative” of the bank today, Group Chief Executive Bill Winters said in a statement.

Tuesday’s settlement extends by two years a deferred prosecution agreement that Standard Chartered originally entered in 2012.

A former Standard Chartered banker in Dubai in the United Arab Emirates pleaded guilty in a New York state court to sanctions-related violations, authorities also said, while an Iranian customer was criminally charged by federal prosecutors in Washington, D.C.

Standard Chartered “undermined the integrity of our financial system and harmed our national security by deliberately providing Iranians with coveted access to the U.S. economy,” Washington, D.C., U.S. Attorney Jessie Liu said.

The agreements resolve an investigation that began into Standard Chartered’s banking for Iran-controlled entities in Dubai. The investigation began roughly five years ago.

The bank paid U.S. authorities $667 million in 2012 for illegally moving millions of dollars through the U.S. financial system on behalf of customers in Iran, Sudan, Libya and Myanmar, some of the same countries involved in the latest settlement.

In 2014, it paid another $300 million to the New York’s Department of Financial Services after a monitor uncovered shortcomings in the bank’s surveillance systems.

In a statement on Tuesday, Standard Chartered said it accepted responsibility for the violations, which stopped after 2014. The bank also said it had cooperated in the investigations.

The latest penalty is a tally of fines and forfeitures imposed by U.S. Department of Justice, the U.S. Department of Treasury’s Office of Foreign Assets Control, the New York County District Attorney’s Office, the New York State Department of Financial Services (DFS), and Britain’s Financial Conduct Authority (FCA).

U.S. authorities will receive $928 million of the penalties, with roughly half of that going to New York.

The FCA imposed a 102 million pound fine ($133 million) on the bank for its control failures. It noted Standard Chartered’s lax controls in opening an account with 3 million UAE Dirham in cash in a suitcase (just over 500,000 pounds) and said the bank failed to get sufficient information about a customer exporting a product with potential military applications.

New York’s DFS said the misconduct involved $600 million in illegal dollar transactions between 2008 and 2014 that moved through the state from the bank’s London and Dubai offices.

Another $20 million in U.S. dollar payments were tied to illegal transactions involving Syrian, Sudanese, Burmese and Cuban entities, the New York regulator said.

After bank employees found that dozens of clients used an internet platform to access U.S. dollar accounts from Iran, bank compliance officers failed to take steps to ensure the transactions were blocked, New York’s regulator said.

Payments from Iran through a fax in the Dubai branch also were not halted, and a manager told an Iranian front company how to evade detection by changing its name and opening a new account, the regulator said.

New York will ensure “the bank lives up to its word and maintains effective safeguards,” said Acting New York Financial Services Superintendent Linda Lacewell. As part of its deal, an independent consultant will continue to oversee the bank’s remediation efforts, the regulator said.

Standard Chartered also agreed to enter into amended deferred prosecution agreements with the U.S. Justice Department and the Manhattan District Attorney for conspiring to violate sanctions and falsifying New York business records. The agreements now run through April 2021.

The bank had been operating under a deferred prosecution agreement with U.S. authorities since the 2012 settlement.

The agreement has been extended numerous times, most recently for 10 days and set to expire on Wednesday.

Standard Chartered said in February it had set aside $900 million for the potential resolution of violations of U.S. sanctions and foreign exchange trading. That sum also included the FCA penalty.

Standard Chartered’s penalty is well below the $8.9 billion imposed by U.S. authorities in 2014 on BNP Paribas for conspiring to evade sanctions. The 10 banks penalized for similar conduct over the past decade also include France’s Credit Agricole, which paid $787 million in 2015, and Amsterdam-based ING Bank, $619 million in 2012.

Reuters broke the news of the latest settlement on Monday and exclusively reported on the probe in 2014.