The U.S. Treasury Wednesday announced measures that could lead to the release of North Korean assets frozen in a Macau bank, Banco Delta Asia, which Washington in 2005 accused of laundering money for the North Korean government.    The controversy over the bank has been a major sore spot in six-nation talks aimed at addressing international concerns about North Korea's nuclear program.  VOA's Stephanie Ho reports from Washington.   

Treasury Department Undersecretary Stuart Levey said Wednesday's action follows 18 months of "in-depth" and "rigorous" investigation into illicit activities he said Banco Delta Asia (BDA) facilitated on behalf of North Korean clients.

"... including activity related to entities facilitating weapons of mass destruction proliferation.  Many North Korean account holders at BDA had connections to entities involved in North Korea's trade in counterfeit U.S. currency, counterfeit cigarettes and narcotics, including several front companies suspected of laundering hundreds of millions of dollars in cash through Banco Delta Asia," he said.

The Treasury, in a two-step decision, ordered American banks to cut off all ties with the Macau bank within 30 days.  At the same time, it will outline risk level assessment guidelines to overseas banking regulators that could be used by Macau to release North Korean funds frozen at the bank.

Washington's investigation into the bank was headed by Deputy Assistant Treasury Secretary Daniel Glaser.  He said the U.S. government has completed its work on the case and will leave it up to the Macau government to decide what to do with frozen accounts worth about $25 million.

"We will provide the Macanese the benefits of our investigation, and we will be providing them with information documentation," he said.  "Ultimately, it will be a Macanese decision as to how to proceed with respect to the funds."

Glaser stressed that he has no expectations as to what the Macau government will do, but said he hopes it will, in his words, "act responsibly."  Macau is a semi-autonomous territory of China.

Retired World Bank economist Bradley Babson, who is now a private consultant, says the U.S. action hurt much more than just Pyongyang's pocketbook.

"The North Koreans were very vulnerable because, I think there were 54 accounts, over $20 million tied up in those accounts, but more important than the amount of money, was this is their system for managing foreign exchange outside the country," he noted.

When the U.S. issued the complaint against the bank in 2005 and the Macau government subsequently froze the bank's assets, North Korea responded angrily and for more than a year refused to participate in the six nation nuclear talks.

The U.S. announcement Wednesday comes exactly 30 days after the six-party nations - the United States, North Korea, China, South Korea, Japan and Russia - reached a deal on Pyongyang's nuclear program.  Under the February 13 accord, North Korea agreed to close its nuclear facilities within 60 days, in exchange for fuel oil and other supplies.

The top U.S. negotiator on North Korea, Chris Hill, is in Beijing, where he is set to review progress on the agreement with envoys from the other six-party nations.

Before those talks, though, Hill meets with Mohamed ElBaradei, the head of the U.N.'s International Atomic Energy Agency.  ElBaradei is also in Beijing after completing a two-day trip to North Korea that he described as "quite useful."