A key South Korean lawmaker says Beijing has frozen North Korean assets on deposit with China's second-largest bank. He says he learned of the move from officials in the United States, which imposed similar sanctions against North Korea, last year. The sanctions are an attempt to combat North Korea's alleged counterfeiting and money laundering.

Park Jin, a senior legislator from South Korea's Grand National Party, told a parliamentary committee in Seoul Monday that China has been cooperating with U.S. financial sanctions against North Korea, by taking banking measures of its own.

Park says Chinese banks have frozen North Korean accounts suspected of being connected to currency counterfeiting.

Park says he learned of Beijing's financial steps from U.S. officials during a recent visit to Washington. He says he was told Pyongyang views the steps as "virtual sanctions," He says the measures went into effect around last November, and were timed to coincide with Washington's blacklisting of Macau-based Banco Delta Asia, which was allegedly assisting illegal North Korean activities.

Park says mainland China's second-largest bank, the Bank of China, has stopped dealing with North Korea altogether. He says Pyongyang is suspected of counterfeiting not only U.S. dollars, but also China's currency, the renmminbi.

Contacted by VOA Monday, China's Foreign Ministry declined to confirm or deny what Park had said.

In a pointed exchange Monday, Park repeatedly asked the South Korean unification minister, Lee Jeong-seok, if he knew about the renminbi counterfeiting, or of China's cooperation with Washington in sanctioning the North. Lee would only repeat that he did not have accurate information on the matter.

Pyongyang has refused to return to six-party talks on the its nuclear weapons programs, giving the U.S. sanctions as its reason. Those talks also involve Japan, Russia, the U.S., South Korea and China.

China has until recently refused to support any kind of sanctions against North Korea, its traditional ally. But Beijing did vote for a U.N. Security Council resolution condemning Pyongyang for its test-firing of a series of missiles in early July. That resolution also imposed limited sanctions on the North.

If Beijing is punishing Pyongyang further, as Park says, North Korea may find itself in the awkward position of a standoff with its major aid donor and trading partner.