TOKYO — North Korea has opened bank accounts in Vietnam and other Asian and European countries that America suspects are used to handle money for illicit arms trade and other illegal activities, a joint intelligence report said.

The American undersecretary for terrorism and financial intelligence, Stuart Levey, traveled to Vietnam on July 18–19 to warn Foreign Ministry and Central Bank officials that North Korea had opened 10 accounts, according to the report, which was obtained by a professor of economics at Japan’s Kansai University, Lee Young Hwa, and shown to Bloomberg News.

“Because of illegal business activities by the North Korean military and espionage organizations, such as the sale of drugs, counterfeit money, and fake tobacco, the country is even losing regular bank accounts,” Mr. Lee said. “This report shows North Korea’s frustration and desperation.”

Vietnam’s central bank is “seriously” investigating money transactions in the country, the report says. A spokesman for the Vietnamese Foreign Ministry, Le Dung, declined immediate comment on the report, which was issued by unidentified agencies in America, Japan, and South Korea.

The U.S. Treasury has been using its authority under international banking laws and the USA Patriot Act to cut off money that it says North Korea gets from drug trafficking and counterfeiting as a way to put pressure on the communist country to stop trying to develop nuclear weapons.

“The U.S. continues to encourage financial institutions to carefully assess the risk of holding any North Korea-related accounts,” Mr. Levey said on August 17. The distinction between legal and illegal money held by North Korea is almost invisible, he said, while declining to comment on his visit to Vietnam.

Mr. Levey visited South Korea, Vietnam, Japan, and Singapore in July to discuss issues such as money laundering and global financial security, according to a Treasury Department statement issued July 18 in Seoul.

North Korea’s Tanchon Commercial Bank and Daedong Credit Bank opened the accounts in Vietnam, and the country has new agreements with 23 banks in 10 countries, including Mongolia and Russia. The report, written in Japanese, says North Korea is opening new accounts after the U.S. Treasury in September said Banco Delta Asia, a Macau, China-based bank, was helping North Korea launder money. Macau’s government took control of the bank and froze $24 million in its accounts.

Japan’s Sankei newspaper published an article Saturday based on the intelligence report.

“There’s a pile of evidence, not just intelligence, but law enforcement evidence, that underlies the fact that North Korea has set itself up as a government willing to accommodate transnational illicit activities,” the coordinator of the U.S. State Department’s North Korea working group to 2005 from 2003, David Asher, said in an interview from Virginia.

Mr. Asher, who is now with the Institute for Defense Analyses, which advises the American government on national security, said it would make sense for North Korea to turn to Vietnam, Russia, and other former communist states once its banking relationships with China were cut off.

Under provisions of the USA Patriot Act of 2001, the Treasury Department may prohibit American financial institutions from doing business with banks designated as money-laundering concerns. At a minimum, the act requires American banks to know the customers with whom they do business.

In 2005, America opened another front in the financial war when President Bush signed an executive order directing the Treasury Department to freeze the assets of those that help distribute weapons of mass destruction, including three North Korean companies. Investigators later froze the American assets of 10 more North Korean entities it said were involved in illegal activities. It has also targeted 13 Iranian entities and one from Syria, a Treasury spokeswoman, Molly Millerwise, said in Washington.

North Korea has protested the financial sanctions imposed after Banco Delta Asia, demanding that America remove them as a condition for resuming talks on giving up its nuclear weapons program.