Canada has urged its citizens to refrain from traveling to North Korea, warning of "extreme risks" for those entering the communist country, a U.S-based media said Tuesday.

Canada's foreign ministry recently re-designated the North as a country for which its people should "avoid all travel," according to Radio Free Asia. The move is based on updated travel information issued by Ottawa.

The alert level is deemed to be the highest among the North American country's four-tier system. The RFA said that Afghanistan, Syria and Mali are among the countries on which the same level of travel alert has been applied.

The RFA said that Canada made the decision, saying that the North's nuclear weapons development and its repressive regime are causing safety concerns.

Tension between Canada and North Korea has remained high since early last year.

A Korean-Canadian pastor has been detained in the North since he entered the reclusive country on a humanitarian mission in January 2015.

In December, the North's highest court sentenced him to life in prison, citing his "subversive plots" against the Pyongyang regime. (Yonhap)