Development of North Korea's economic development zones has come to a standstill since the reclusive country carried out its fourth nuclear test early this year, a U.S.-based media report said Wednesday.

Citing a professor in South Korea, the Voice of America said Pyongyang has failed to induce foreign firms to come set up operations in its special economic development districts, despite its desperate efforts to attract investments, especially from its key ally China.

The United Nations Security Council slapped its toughest sanctions to date on North Korea for its nuclear test in January and long-range rocket launch in the following month.

VOA's report was made on the basis of a remark by Lim Eul-chul, a professor at the Institute for Far East Studies of Kyungnam University in South Korea.

According to the professor, North Korea engaged in vigorous business activities for various economic development projects last year, but so far this year it has not been able to draw in investments due to the international sanctions imposed on the country.

Before the nuclear test, North Korea reported that foreign firms showed interest in holding business talks, particularly in regards to the Mubong and Onsong economic development zones, which are located near its border with China.

Curtis Melvin, a North Korean economy researcher, said in an email to the VOA that there has not been any notable change in the North's economic zones as judged by satellite imagery.

Melvin is a researcher at the U.S.-Korea Institute at Johns Hopkins University and a contributor to 38 North.

North Korea has established a total of 28 economic development zones since a special decree was legislated in May 2013.

North Korean leader Kim Jong-un emphasized the importance of pushing for the development districts in his New Year's address in 2014. (Yonhap)