The alleged financial transactions contributed to Kim Jong-un’s illicit procuring, and exporting, of its ballistic missile system, according to a report by Voice of America.
Under US sanctions, the bank is barred from the American financial network, and prohibited from opening or keeping a bank account in the US.
Latvian foreign minister Edgars Rinkevics said: “We are working to investigate this issue. While the investigation is not over, I cannot go into specific details.
“We are working with the US government.”
He also affirmed his country’s compliance with UN sanctions on North Korea.
He said: “We support all the sanctions.” Mr Rinkevics’ comments followed his talks with Foreign Minister Kang Kyung-wha in Seoul.
The pair welcomed the establishment of the Baltic States-South Korea economic cooperation committee, which is expected to further strengthen economic relations.
During their conversation, the Ministers also shared views on cooperation in international organisations and on regional issues, including the situation in the Korean Peninsula.
After a meeting with President Moon of South Korea, Latvian President Raimonds Vejonis said the security situation in the Korean Peninsula must be resolved in a peaceful and diplomatic manner.
Speaking about the security situation in the Korean Peninsula, Vejonis stressed the need to find a peaceful and diplomatic solution, while condemning the provocative actions and rhetoric by North Korea.
He said the recent high-level talks between South Korea and North Korea is a positive step towards a peaceful solution.
President Moon asked for Latvia’s support for his efforts to build on the conciliatory mood formed between the two Koreas after the PyeongChang Winter Olympics thaw in relations to create the conditions for denuclearisation talks, officials said.
Noting that Mr Vejonis is the first Latvian president to visit South Korea since the two countries established diplomatic relations in 1991, Moon called for using the visit as an opportunity to further enhance relations with Latvia.
Mr Vejonis said in response he hopes the relations will be strengthened with a focus on trade and investment.