Bank of China is cutting off business with a bank in the Democratic People's Republic of Korea accused by the US of assisting Pyongyang's missile and nuclear programs.

A Bank of China spokeswoman said on Tuesday it has told the DPRK's Foreign Trade Bank that its accounts are being closed and all financial transactions suspended.

The Foreign Trade Bank is the DPRK's main foreign exchange bank. In imposing sanctions against it in March, the US Treasury Department described it as a "key node" in financing the DPRK's weapons programs. The US sanctions prohibit any transactions between US entities or individuals and the Foreign Trade Bank. Japan has followed suit, while Australia is expected to do so soon. Washington has also urged the EU to impose sanctions.

A spokesman for China Construction Bank said the bank does not do any business with the Foreign Trade Bank.

Industrial and Commercial Bank of China and Agricultural Bank of China were not immediately available for comment.

AP-Reuters