The top U.S. envoy for North Korea will travel to Moscow this week for talks on dismantling North Korea's nuclear weapons program, the State Department said Tuesday — a sign that a meeting between leader Kim Jong Un and Russian President Vladimir Putin in the near future could be imminent.

Stephen Biegun, who is in charge of working-level negotiations with Pyongyang, was due to visit Moscow on Wednesday and Thursday to meet with Russian officials and discuss "efforts to advance the final, fully verified denuclearization of North Korea," the State Department said in a statement.

The visit comes amid unconfirmed reports that Kim and Putin will hold their first-ever summit in Russian next week.