North Korean banknotes have plunged in value against China's yuan.

The new banknotes, which were introduced a month ago, have been subject to negative discussion by North Koreans, causing the new won to depreciate against Chinese money.

The banknotes were produced in a move to knock two zeroes off the currency.

South Korea's Yonhap news has reported that by late December, traders on China's border with the North were exchanging 1,000 North Korean won per Chinese yuan, compared to 50 per yuan on December 3 after the notes were launched.