The head of North American affairs bureau of North Korea’s Foreign Ministry has arrived in Berlin to attend a closed-door forum between U.S. and North Korean officials.

Ri Gun arrived at Berlin’s Tegel Airport on Thursday afternoon, local time, from Beijing. Asked by reporters at the airport about the agenda of the upcoming meeting, Ri said he had no comment and got out of the airport to head to the North Korean embassy in Berlin.

An official of the U.S.-based Aspen Institute that greeted Ri at the airport said a news conference will be held after the forum is over.

The Aspen Institute will hold private debates this weekend and early next week where North Korean officials and former senior U.S. officials will discuss U.S.-North Korea relations and the North’s denuclearization among various issues that concern the Korean Peninsula.