A high-ranking Seoul official says that South Korea first proposed the creation of a working group with the United States on North Korea's denuclearization. 

The Foreign Ministry official made the revelation on Wednesday in a meeting with reporters, hours after Washington announced the launch of the new consultation body with Seoul. 

Noting that having such an entity will likely raise efficiency of the related negotiations, the official said the South had been discussing its creation for several months with U.S. Special Representative for North Korea, Stephen Biegun. 

The U.S. State Department on Tuesday announced the launch of the working group, which it said would further strengthen coordination on denuclearization, sanctions implementation and inter-Korean cooperation that comply with UN sanctions.