A South Korean delegation may not be able to visit North Korea on a chartered plane for a planned joint ski training session due to U.S. sanctions on the North.

A Unification Ministry official said on Wednesday that coordination with the U.S. on the matter has not been finalized yet, adding it may be difficult for the delegation to visit North Korea using a chartered plane. 

The delegation was scheduled to take a chartered flight from Yangyang Airport in the South's eastern province of Gangwon to Kalma Airport in the North Korean city Wonsan on Wednesday for a two-day training session at the North's Masikryong Ski Resort. 

But the flight requires U.S. consent as Washington announced a set of sanctions on the North in September last year, which include banning vessels and aircraft that have visited North Korea from entering the U.S. within 180 days.