A United Nations agency for telecommunications said Saturday it has not been notified of North Korea's bid to change its standard time, amid rising concerns the move may further isolate the country.

The remark came as North Korea said Friday it will push back its standard time by 30 minutes to mark the 70th anniversary of liberation from Japan's colonial rule. Accordingly, North Korea's clocks will be moved back a half-hour starting on the upcoming Aug. 15 anniversary.

Currently, the two Koreas use identical standard time, set under the colonial period.

The International Telecommunication Union (ITU) said North Korea did not notify it of the plan prior to the announcement, adding that the decision was made independently, according to Radio Free Asia (RFA).

But the ITU said countries are free to follow their own standard times, adding it cannot force North Korea to stop the move.

From 1910-45, Japan colonized what are now the two divided Koreas before the peninsula became independent with Japan's defeat in World War II on Aug. 15, 1945.

The ITU, a U.N. agency, deals with technological issues, which includes global standard times, radio frequency allocations and improvements in communications services. (Yonhap)